According to ABC 7, the teen recorded herself singing what's believed to be her own songs that have a common theme: sadness.
"You blame me for everything, you blame me in every way, you blame me for what they say, what they say", one of the songs went.
Her most recent post went up just seven days before she escaped through a window of her Perris home in January to alert police that she and her siblings were being held captive by their abusive parents.
The clips also give some insight into the conditions inside the home, with one showing a huge pile of clothes in the corner of a room and dirt smeared on the door.More news: Ankara, 'end of Afrin offensive by May, then Iraq'
The teen's Instagram account shows mostly selfies and also includes some photos of Justin Bieber.
Officers responding to the scene found her 12 siblings ranging in age from 2 to 29 inside, suffering from malnourishment, muscle wasting and other signs of severe abuse.
Another clip shows the girl playing with the family's two dogs, who authorities say were treated better than the children themselves.
"They're starting from very elementary stuff", she said, but have "progressed very, very well".More news: Cheerleaders possibly exposed to mumps in Dallas
In a case that sent shockwaves across the world, investigators are still searching for a motive behind the alleged abuse of 12 of the children.
The parents, David and Louise Turpin, face up to life in prison if convicted of a combined 78 charges, including torture, false imprisonment and child endangerment. Mr Turpin is also facing a single charge of a lewd act against a child by force or fear. "He would sob like his shoulders would shake up and down ... when mentioned about his parents and his brother and not seeing them", she said.
The children were allegedly chained up for months at a time, allowed to shower only twice a year and denied access to a toilet. They said the couple shackled the children to furniture as punishment and had them live a nocturnal lifestyle.
Louise Anna Turpin, far left, with attorney Jeff Moore, center, and her husband David Allen Turpin, listen to attorney, David Macher, as they appear in court for their arraignment in Riverside, Calif., Jan. 18, 2018.More news: Sing to the new baby, Oxford schoolgirl advises Duchess