What do you read into the MIL's message?

A typical IL response all the way. She says she is unhappy but unwilling to stop her daughter from rolling around in the pig pen mud. She might get her sundress dirty if she gets too close.

All I got from my IL's of 25+ years was a tiny measure of personal (not moral) support to appease their own guilt.

I would not look too deep into it Gurka.

Testosterone boys! Testosterone! It aint just for nose, ear and back hair anymore!