The Wisconsin family posted the update on a fundraising website, which raised about $22,000 (Â£13,000) in less than a day for her legal and medical bills.
Her two alleged attackers, classmates Morgan Geyser and Anissa Weier, have been charged with attempted murder.
They told police they were trying to impress a fictional character called Slenderman, according to officers.
Doctors said the knife had just missed a major artery near her heart.
"Our little girl is a fighter and is making strides of improvement each and every day," her parents wrote on the website, but added they were limiting visitors as she was easily overwhelmed.
"She has been able to walk the halls of the hospital with her dad. No machine, no tubes, just she and her dad. She has been out of bed watching TV in her wheelchair as well."
They are hoping to raise $250,000 in total for legal and medical costs and have asked to keep the girl's name secret.
The victim was reportedly found by a cyclist on Saturday after crawling from the woods with stab wounds to her arms, legs and torso.
Both suspects were later found walking near a local highway, and a knife was found in one of the girls' backpacks, police said.
According to police, the girls planned to stab the classmate during a sleepover but instead decided to commit the crime the next morning in a nearby park.
Following their arrest they told investigators about their belief in paranormal figure Slenderman and their desire to become his "proxies" by killing to demonstrate their loyalty, police said.
They said that after the murder, they intended to walk to Slenderman's mansion, which they believed was situated in Wisconsin's Nicolet National Forest, police said.
The family of a 12-year-old stabbed 19 times says she is able to walk in hospital and making a steady recovery.