I am a MOH planning my best friend's lingerie shower/bachelorette. Her FSIL is a bridesmaid and they are on good terms but I don't think they're very close, I think she was definitely asked to be in the party as a concession to her FI's mom. Should I invite her? I can see that FSIL might feel weird about watching my friend open all this sexy underwear knowing who'll be "appreciating" her in it... but I don't want there to be a controversial hissy fit with my friend's FMIL about how I'm a bad MOH and left FSIL out. So do I invite her or not?