Can you maybe direct her towards other stuff that will be useful or even a range of sizes so bub can grow into them? It's easy to go nuts on the clothes because they're so cute, but you're right, half the time they barely get worn by the time bub grows out of them.

I'm trying to direct my MIL and family into things like joining together for bigger things like an ergo carrier, travel cot or such like. So far it seems to be working