-- The way Nana the pit bull smiles today, no one could probably ever guess the horrific abuse she had to overcome during the first eight years of her life, according to her owner, Stephanie Doris.
"When I first fostered her in February of 2013, she was eight years old, and she had just been surrendered after having been used for breeding her entire life," Doris, 25, told ABC News today. "She had about 14 to 15 litters, and she was so sick."
"It was supposed to be a two-week thing -- I was just going to get her healthy and then adopted," Doris said. "But those two weeks turned into months and then after six months, someone serious about adopting her came forward. I realized I couldn't let her go, and she's been with me ever since."
Nana "has been through the ringer," Doris said, but she's recovered tremendously and has remained "magical, loving and sweet" despite the multiple rounds of antibiotics and surgeries she's gone through -- including one to remove her ears due to the pain.
"She's deaf now, but she's so much happier," Doris said. "She completely transformed after that surgery and just blossomed."
Doris added that she credits her family's dog, a German Shepherd mix named Zyra, with "teaching Nana how to be a dog again."
"Zyra was two at the time I adopted Nana but Zyra still acted like the big sister," she said. "Whenever I let Zyra outside, Nana followed along. Whenever Zyra barked, Nana would bark. They were a dynamic duo."
Doris added that though she moved to Henderson, Nev., for medical school, she and Nana still go back to the Los Angeles area to visit Zyra once a month.
"When they're reunited, they will cry and kiss and run around," she said. "It's really sweet."
Nana is still battling the skin cancer she likely developed "from being kept outside 24/7 by her previous owners," Doris said, adding that though she's frustrated and mad at Nana's original owners, she's learned a lot about forgiveness.
"Nana has forgiven people, and she's learning to trust new people now," she said. "A few months ago, she'd run the other way from a stranger. Now, she'll let a new person come up to her and pet her. She's forgiven people, so I have to also.
"And if it weren't for her original owners, Nana wouldn't have ever come into my life, as cheesy as it sounds. She's a blessing, the epitome of forgiveness and hope," Doris added.
The 25-year-old said that aside for the cancer, Nana is otherwise healthy and is actually "getting healthier as she gets older."