I have heard of these cases before. It will be interesting to hear from people in this situation. Is there a biological sibling? In that case, there is an argument because the child should have contact with sibling. Also, does stepmom and child have a strong relationship? Sounds like there is tension, and I know that it is frustrating when threatened with court, but when stepparents are a part of stepchild's life from a young age there is a bond (I know there's bonds in lots of other cases too). I see this situation from both sides, since
DH is extremely bonded with son (his
SS) partly since he was involved from birth. And son's stepmom, who was also involved from birth, is always fighting with me because she wants to be acknowledged as important (really is a complex on her part though, I have assured her many times that I respect her role in my son's life. But it is annoying.

)
Anyway, to answer the question, he can always file for a modification. If there is a significant change in circumstance, then the judge will hear it. My approach is to see what he does and then go from there. If he files and you don't want to go to court, you'll prob have to reach a compromise of some sort.