Background: FIs dad has been in and out of the picture, in and out of jail, definitely not a "father-son" relationship. FI's mom died about 4 years ago, and they were divorced years before that. FI's dad basically stopped any parenting at that point. He will disappear for months at a time. Until the other night we hadn't spoken to him since Christmas.
FI's uncle called us about the wedding and FI's dad happened to be around and want to talk to us (a rare occurrence). FI's dad then mentioned that he was brining a "big tittied stripper" as his uninvited guest (FI insisted no guest). Off the top of my head I said "Well, make sure to RSVP with her name so I can make her a proper place card"
FI is convinced he is joking, and we haven't received his RSVP (honestly, not that I'm expecting to, given his track record) but it still wouldn't surprise me if he showed up at the wedding with, well, a big tittied stripper.
I know it is beyond my control, and it will not make a difference at the end of the day in whether we are married or not, but c'mon! That is not what I want for my wedding!
OK, I'm done, and over myself

Any advice (including "suck it up") is very welcome! Thanks!