Re: Another MIL post..WWYD?
Oh for Pete's sake. People like her just drive me nuts. She obviously doesn't love her son enough to behave like an adult, respect his family, or let him enjoy this special time. I think you have the right idea. He does not have to send the thank you. I would send her a SUPER generic card like you mentioned.
Thank you for the "..." and sign The "...." Family or just your first name.
If your husband does not want to keep the gift you could donate it to charity. We have done that before. We have also shipped things back but with you being overseas that would be too much. Perhaps you could speak w/ step MIL about blocking MIL so that some of this drama will not continue? We do not have Facebook for this very reason. Congrats on your baby
Just in case.