I'm trying not to make a big deal of it in my head. And since she's flaky, the odds of her actually showing up are slim anyway. But it gets under my skin because 1) we made a conscious decision to only invite the grandparents, because we wanted to keep it small, 2) FIL thinks it's fine to tell DH "by the way, your sister is coming, too"--not asking, but telling, and 3) DH, who has no problems speaking up when it's just us, goes mute whenever his dad is involved. It's a whole approval-seeking thing because he felt rejected when his dad wasn't involved when he was younger, so I try to understand, but cheez whiz.
Logistically, it's not a problem--it's not like feeding one more person changes anything. But the control freak in me doesn't like other people telling me who's coming to my party. That's what it boils down to.
We also had a conversation about family customs, because in DH's family people just come over, whereas in mine, you would never dream of showing up for a aprty unless you'd been invited. Two extremes, and I'd like to be somewhere in the more moderate middle.
::builds a bridge and starts getting over it::
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