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Carmella, a pit bull, was rescued by Sandy Roberto, owner of Must Love Dogs in Wayne, New Jersey. The dog grooming shop owner told ABC News the disabled dog had been in her care for over a year. Carmella suffers from spinal problems, and her legs are bowed out. A veterinarian told Roberto that Carmella developed the deformities from being kept in a small cage as she grew.

When the twin girls' mother, Dana Polito-Corry, asked them what they wanted for Christmas, Tianna told her, "I want a disabled dog for Christmas." She went on to say, "I'm very different in school. I'm the only one who walks with a cane and I wondered if I got a disabled dog, she would know the same feeling," reported CBS New York.

Polito-Corry was at Must Love Dogs getting one of her other dog's nails trimmed when she jokingly mentioned the Christmas wish to Roberto.

“I was explaining my daughter’s Christmas wish — kidding around — and almost on cue, Carmella walked over," she said.

Polito-Corry immediately loved the dog before she knew about her disability.

Once Carmella got along well with Polito-Corry’s other dogs, the adoption was set.

The twin girls were surprised and excited to welcome the pit bull to their family. When they met, Carmella was dressed in a red Santa suit. The first thing she did when she got to her new home was jump on the bed.

"She's already feeling at home," Polito-Corry told ABC News.

Shortly after joining the family, Carmella is already helping the girls. Polito-Corry said Gianna rarely spoke before the pet adoption, and now, she likes to talk about Carmella. Tianna has social anxiety, and the new pup helps her ease into conversations with people.

The family has encouraged others to adopt dogs who are differently abled.