SAN MARCOS, Texas -- A puppy that was brought into the San Marcos Regional Animal Shelter last month is making a comeback. It's been about a month since "River Faith" arrived, and she's already made milestone improvements.

The shelter staff said they believe she was dropped off near a river, but have no way of knowing how she got there. A concerned citizen found her and brought her to the shelter. The puppy weighed in at just seven pounds back in mid-June, and is now at a whopping 13 pounds.

The staff decided she looks the most like a "Chiggy" breed, which is a Chihuahua mixed with an Italian Grey Hound. This girl has come a long way, with her ribcage no longer showing as she continues to regain muscle.

While she's made strides, she's got a long road ahead in the manners department. Once she's ready, the shelter will place her with a patient family, because they said she'll test every limit set for her.

In the meantime, anyone that wants to can donate either supplies or make a financial donation to the shelter. Animal Protection does not have any information on related to the cause of Faith's malnourishment, and ask if you do to contact them.

"The only leads we had ended up going nowhere so we don't know where she came from how she got that way, so that's really difficult for us because we don't have anybody to ask what happened we just have to go off of what we have. Thankfully, the vets can run a lot of tests and make that happen for us," said Erin McCann with San Marcos Regional Shelter.

She's already got a long list of potential adopters already and could be in her forever home as early as next week.​