Background:
I am a US citizen and I've previously petitioned for my spouse to immigrate on a K1 visa. They brought their child with them on a K2. Both spouse and child have adjusted status and are conditional LPRs. They are in the process of lifting conditions.
My spouse has another child in their home country that did not immigrate due to living with the other biological parent. We recently found out that the child is currently in foster care and wish to pursue bringing them to the US.
From my research, our options are a F1 visa (if the US citizen (me) sponsors the petition, this is a stepchild relationship) or a F2A visa if the spouse LPR sponsors the visa.
Is my research correct and which visa, if both are available options to us, is the faster option for bringing the child to the US.
Is there a faster option to legally bring the child into the US? Our highest priority right now is the child's safety.