The team at Gray Animal Hospital is here for all your pet’s needs. Call (224) 304-0668 or use the online form to book an appointment for your pet!
Tonya Gray
DVM, Owner

Dr. Tonya Gray received her Doctorate of Veterinary Medicine from the University of Illinois Urbana-Champaign in 1998. Her areas of interest include dentistry, having completed extensive training from the University of Wisconsin Madison, and emergency surgery. She holds professional memberships with the Chicago Veterinary Medical Association (CVMA), the American Veterinary Medical Association (AVMA), and the Illinois State Veterinary Medical Association (ISVMA).
Dr. Gray chose her career path for the love of science and pets. She knew veterinary medicine was the right fit since high school and enjoys nurturing close, longtime bonds with families as they care for pets. Her most rewarding experience in her career is opening Zion’s first animal hospital and offering residents affordable veterinary care that’s also state-of-the-art.
Dr. Gray married her husband Rick the same year she started veterinary school. Raising their three sons, Ricky, Derrick, and Benjamin, is her greatest life accomplishment. When she’s not busy helping pets and their families, she’s cooking for hers, watching her sons play sports, weight training, or running – she recently ran her first half-marathon.
Linda Lewiston
Associate Veterinarian

Dr. Lewiston earned her DVM from Iowa State University in 2009. She then completed a small animal rotating internship at Animal Emergency and Referral Center in Northbrook, IL. She is a graduate of the Karen Pryor Training Academy and is a certified training partner. Prior to becoming a veterinarian, she worked as a high school science teacher, a junior high/high school guidance counselor, and an emergency medical technician for a hospital-based ambulance service. She got into veterinary medicine because she had a cat that started having seizures. The veterinarian that took care of her encouraged Dr. Lewiston to become a veterinarian, and so she did! In her current role, she enjoys working with animals and giving them the best quality of life possible. She believes that in order to work with animals, you must work with the owners, and that can be extremely rewarding!
At home, Dr. Lewiston has two Boxers and four Golden Retrievers. She and a friend breed Golden Retrievers and many of the puppies have become service dogs. One is even a drug sniffing dog with a police department! She enjoys doing conformation, obedience, and agility with her dogs and has earned obedience titles and good citizen titles for many of them! She also works with many rescues to help dogs who have behavioral issues become better suited for adoption. In addition to her dogs, she has multiple cats that are all rescues who needed a place to call home! In her spare time, she enjoys curling up with a good book and cat on her lap.
Brittani Gimenez
Associate Veterinarian

Dr. Brittani Gimenez earned her Doctor of Veterinary Medicine (DVM) degree from Kansas State University CVM in 2018. She received the Pet Tribute Scholar Award for her outstanding compassion toward pet owners who have suffered the loss of a pet.
Her journey began when she cared for a stray kitten with an eye infection during her childhood. This experience solidified her commitment to working with animals and providing them with the best care possible. She believes in trusting your instincts as a pet owner, advising clients to trust themselves as they know their pets better than anyone. If something doesn’t seem right, talk to your vet!
An important thing pet owners should know is that some foods are sweetened with xylitol, a sugar substitute that can be toxic to dogs. Xylitol can lead to potentially fatal hypoglycemia if ingested and is often marketed as “birch sugar.” Dr. Gimenez emphasizes the importance of being aware of this and other health hazards to keep pets safe. She is passionate about educating pet owners on vaccines, health conditions, and preventative care, ensuring pets lead healthy and happy lives.
Dr. Gimenez comes from a family of dentists, including her father and grandfather. She has always had a special interest in veterinary dentistry and enjoys discussing interesting cases with her dad. At home, she has two dogs: Jasmine, a 10-year-old Black Lab, and Shadow, a 15-year-old Chihuahua. Jasmine is her running buddy, while Shadow is her snuggle buddy. Despite their different energy levels, both dogs are very sweet and great with people and kids.
In her free time, Dr. Gimenez enjoys walking, jogging outside, reading, cross-stitching, and playing video games. She is proud to be part of the veterinary profession and also takes pride in being a mother and wife. Her supportive husband has been by her side through vet school and beyond, and she loves playing with her daughter when she gets home from work. Dr. Gimenez’s favorite food is popcorn, and her favorite book series is Harry Potter. She grew up with miniature Schnauzers and will always have a soft spot for this breed.
Kelly
Veterinary Technician

Since she was a child, Kelly has had all kinds of pets at home. She remembers seeing stray cats and sneaking out of her bedroom window to feed them. Going to the vet was one of her favorite things to do. In Colombia, she attended one of the best universities and graduated as a DVM and worked as a vet for two years. Since moving to the US to be with the rest of her family, she is in the process of validation and in the mean time, holds First Aid certificates for Dogs and Cats and also has a Diploma in Urgent Care and Emergencies, Respiratory Therapy and Critical Care for Small Animals. The most rewarding part of the job for her is knowing that she is helping save lives every single day. She prides herself on always achieving what she sets out to do and having a big heart.
When not at work, Kelly loves spending time with her husband, their Husky Zeus and their two cats Almendra and Dali. She also loves to travel and go shopping in her free time.
Cindy
Practice Manager

Cindy is excited to be at Gray Animal Hospital and she looks forward to working with our team and our patients. What she finds most rewarding about her position is being able to work with so many great people and helping in any way she can—she’s a people person, and she loves helping others. Cindy married her high school sweetheart, Jeff, and they now have three grown children and three grandchildren. She’s extremely proud of them, and could not ask for a better reward in life. Cindy and her husband also have two pets; a Yellow Lab named Phoebe and a male Butterfly Betta named Fin. She loves spending time with her family, along with doing needlework, babysitting her grandkids and watching the Chicago Blackhawks.
Brenda
Veterinary Technician

Brenda has always wanted to work in the animal care industry since she was young. She is certified as a veterinary assistant and is currently enrolled in a course to become a certified veterinary technician. Her favorite part about her job is having the opportunity to help animals that are sick.
Brenda and her husband have three pets including Lobo, a German Shepherd, Tinkerbell, a Maltepoo, and Miso, a Holland Lop bunny. In her spare time, she enjoys painting (using acrylic, watercolor, and oils), going to concerts, and watching action movies.
Heather
Veterinary Technician

Heather earned her bachelor’s degree in sociology from UW Parkside. Since she was a child, she has always loved animals and caring for them. She especially loves the bond between humans and animals, and how much joy they can bring to our lives! The most rewarding part of her career is being able to provide compassionate care to the animals she sees.
Heather is married to her husband, Dustin, the best dog-dad ever! They have an energetic Boxer named Mia who they just love and adore! In her spare time, Heather enjoys pottery, baking, working out, and spending time with family. Oh, and eating chocolate! She and Dustin also love movies and her favorites are comedies, and the movie, Jaws. She also loves to watch Shark Week!
Maria
Veterinary Technician

Maria received her DVM from the Universidad Autónoma de Zacatecas in 1987. She chose to become a veterinarian because of her father. She grew up on a ranch and helped her father care for the animals, and that’s how her love for them grew! In her current role, she loves helping with surgeries and seeing pets improve while in her care.
Maria and her husband, Francisco, have two children, Grecia who is studying for her master’s degree, and Francisco who is finishing his undergraduate degree. They have a dog, Milo, an Australian Shepherd, Pancholin, a cockatiel, and many fish! In her spare time, she enjoys listening to music and reading. One of her greatest accomplishments in life has been coming to a new country and having her children understand and be a part of two cultures.
Marlena
Veterinary Technician

Marlena has always loved animals, but it wasn’t until she go her first dog, a Boxer named Pacman, that she decided to work with them. She received her Vet Tech Certification from the University of Wisconsin and currently has 3 dogs, 4 cats, 5 tarantulas, 1 snake and 1 lizard.
In her free time, she enjoys reading and loves spending time with her husband and 3 children. She considers raising her kids to have the utmost respect and care for animals her greatest life accomplishment.
Ariana
Veterinary Assistant

Ariana has been around animals her whole life. On mission trips, she would often have dogs following her around, and that made her realize she was meant to help those who can’t speak for themselves. Ariana took the CLC assistant program before taking on the vet assistant role here at Gray Animal Hospital. As part of our team, she loves learning something new every day and being an advocate for animals and their owners. At home, Ariana has 3 dogs: Shelly the Maltese, Coco the Cavalier King Charles Spaniel, and Trixie, a Pom-Chi. When she isn’t working, Ariana enjoys singing with her worship group, taking photos, and spending time with her friends and family.
Ashley
Veterinary Assistant

Ashley always loved animals and would do anything she could to help them, even at a very young age. She has an associate degree in applied veterinary sciences and enjoys using her knowledge and experience to help patients get better and educate owners on how to better understand their pets. She and her husband share their home with Gidget, a Dachshund, and they enjoy spending time outdoors together. Ashley also loves watching movies, going fishing, playing board games, and just spending quality time with her family.
Chad
Veterinary Assistant

Chad started out working at a small-town animal clinic while he was in high school, and this made him realize he truly enjoyed pet care. He also spent some time working at a dog daycare center, but he missed the medical side of things. So he joined the Gray Animal Hospital team and has been learning and growing ever since! He loves seeing sick or injured animals come back happy and healthy.
In his free time, Chad loves doing art projects, aquascaping freshwater tanks, and taking naps.
Bridgette
Veterinary Assistant

When she was a kid, Bridgette had a Holland Lop rabbit that inspired her to pursue a career in the veterinary field. She absolutely loved caring for her rabbit, and she also had gerbils, dwarf hamsters, birds, hermit crabs, and turtles while growing up! In 2021, Bridgette earned her veterinary assistant certificate from College of Lake County. The most rewarding part of her job is getting to take care of animals and help them feel better. Outside of the practice, Bridgette loves gardening, baking (homemade brownies are one of her favorites), drawing, and playing video games.
Monica
Veterinary Assistant

Monica decided on a career in veterinary medicine due to the passion she has for animals. She believes that her greatest life accomplishment so far has been to professionally work for the care of animals.
At home, Monica lives with her family, Alex, Alex Jr., and Kassandra, as well as their pets, Diesel, a German Shepherd, and Guillermo, a green checkered bird. When she has time, Monica enjoys reading, spending time with her family, and exercising.
Bobby
Veterinary Assistant

Bobby holds degrees in both Zoology and Immunology from WIU. His favorite part of Veterinary Medicine is seeing pets return to their happy, giddy selves after being treated. He also enjoys meeting people through his position.
Bobby has a spicy calico cat named Merlot, and enjoys reading, hiking, writing music and studying martial arts in his free time.
Kim
Customer Service Representative

Kim grew up with many pets, and in a family that also loved pets. She always loved going along to all their veterinary appointments! Kim has been a receptionist for 30 years, and cannot imagine doing anything else. She loves her career, her coworker family, and all the wonderful people and pets she’s had the pleasure of meeting over the years. She treasures the relationships and friendships she has built during this time, and enjoys helping educate people to help their pets live their best lives.
Kim’s four-legged best friend is Helmi, a Rottweiler, with whom she enjoys taking walks and sitting on the sofa with her boyfriend, watching a movie with a fire crackling in the fireplace. Her other hobbies include bicycling, reading, doing yard work, and walking her dog.
Francisco
Customer Service Representative

Being in a position to help pets in need is one of Francisco’s favorite things about his job. He has 2 four-legged family members of his own, an Australian Shepherd named Milo and a cockatiel called Pancholin.
Outside of work, Francisco’s hobbies include going to the gym, painting canvases, and thrifting. Some of his other favorite things include Disney’s Hercules and Colombian empanadas.
Yvonne
Customer Service Representative

Yvonne joined our practice out of her love for animals, and is grateful to have the opportunity to work with the caring individuals here at Gray Animal Hospital. She has 3 dogs of her own at home; 2 English Pointers, Rosebud and Navarre, and a Treeing Walker Coonhound named Sunny D. In her spare time, Yvonne trains dogs (she has proudly certified 2 search and rescue dogs so far), and she regularly participates in dog shows.
Olivia
Customer Service Representative

Olivia worked at the Wisconsin Humane Society for 5 years before joining the Gray Animal Hospital team (and she still works there when needed). She loves helping people and pets! Olivia has 2 pets who make her house a home: Pico, a Staffordshire Terrier/Lab/Husky mix, and Pawl, a brown and white tabby. When she isn’t working, she enjoys spending time with her family, watching sci-fi and supernatural shows and movies, and playing video games.
Amarr
Kennel Attendant

Amarr’s decision to work in veterinary medicine stems from his love of animals. He also genuinely likes the people he works with each day here at Gray Animal Hospital. While he doesn’t have any pets of his own, Amarr does get to care for a wide range of dogs and cats, so he can’t complain. When he isn’t working, he enjoys reading, watching football, and listening to music. Amarr also loves food and has a great sense of humor.