When Zipper arrived at a shelter after being found wandering the streets as a stray, staff noticed that the 8-year-old canine was unusual. She’s a normal dog with a great, friendly personality — except she has a deformed jaw that gives her the most charming, one-of-a-kind grin.

According to Huntsville Animal Services personnel, Zipper’s distinctive smile appears to have no impact on her. She eats regularly and enjoys rewards, and she appears to be unaware that she is unusual.

“We don’t know what caused the jaw malformation,” Erin Webb, a volunteer with Huntsville Animal Services, told The Dodo. “We have no idea what caused it.” She does have a big underbite and her teeth are pretty far apart.”

Zipper was most likely an outdoor dog her whole life and was not appropriately cared for, based on her state when she appeared at the shelter. She has severe fur loss as a result of flea allergies, and she seems to have had numerous litters of puppies in the past. She may have been discarded because she was no longer desired or needed, but her new shelter family recognizes how precious she is and can’t wait to help her find a forever home.

Zipper may seem distinct from other dogs…

… yet when you see her unusual grin, you can’t help but want to get to know her.

“Because she is an aging dog, she is a quiet and kind girl,” Webb explained. “She tends to favor snuggling over traveling.” She likes to play with the other dogs and has made friends with Mr. Mike, our other old dog.”

Zipper gets along with other dogs and appears to get along with children. She has a really beautiful, kind nature and would likely do well in a variety of households, according to the shelter. Zipper has probably had a difficult life, and she’s looking for a place to retire with a family who will accept her for who she is.