gifts for parents and FIL

My parents have been great during the whole wedding planning process....but my FIL's haven't done anything at all... they don't ask about it, offer to help plan or anything..

So my question is...what gift do we buy for my FH mom and her husband(not FH father) ?
we don't even know if they will show for the RD where we plan on giving out the gifts....



any advice or anything would be great.

Jess