Courts also appoint guardian ad litems (or guardians
ad litem, which is probably the more correct plural form) in cases besides (financial) child support.
As a young lawyer I volunteered some of my time to help my city's guardian ad litem (lawyers hired for a term to be the guardian ad litem in that judicial district).
I did not do it for very long (maybe six months), because I did not like the lawyers, and because I did not feel qualified to make the judgments they wanted me to make. I still remember one case (my final one) in which I was sent by appointment to a home to try to determine whether the father was sexually molesting his daughter who was then about eight or nine years old.
I spoke at some length with the little girl and tried to find out whether she was safe, but, not being trained for such investigatory work, I could come to no clear conclusion about whether the father was doing bad things to her or not. I suspected Yes, but I did not want to guess about such a horrible accusation.
In any event, the right spelling is guardian ad litem.