Most of the kids I’ve looked after have returned to a biological parent. This usually happens within six months to a year. Sometimes, though, the parents are unable to get their act together, and after about 18 months the county switches from trying to reunify the child with his or her parents, to trying to find a permanent, stable home for the child.
This has happened to me twice so far. The first time was with my third full-time foster child, and it was quite traumatic. He was placed with me just before his 11th birthday. Within a year his mother was murdered while trying to purchase her drug of choice, methamphetamine. From our perspective, she just disappeared one day. Months later a fisherman found her body wrapped in a carpet.
I became the legal guardian of this boy and he stayed with me until he was 19 years old.