In light of the recent rash of threads about it, I thought we could have a compilation thread to keep them all in one place.
I'll start with my wedding, and my SIL.
We wanted her DS (who was about two and a half) to be a sort of page boy and wear the same style suit as his dad (best man) and the rest of the 'wedding party' including my DS. SIL said no as he woudn't want to wear a suit. And then promptly went out and bought him, that's right, a suit to wear.
She then asked if we could arrange a vegetarian meal for her despite the fact she is not a vegetarian. Which of course we did, although it smacked of 'making life difficult'. And she then managed to take both veggie meals on the day leaving my actual veggie cousin without a meal (still not sure how this happened).
At the ceremony she brought her DS in eating the World's Biggest Icecream? which he then sat and slurped in his non matching suit all through the vows.
When we got to the venue she moved all the place settings around because she didn't like where she was sitting.
She then got very drunk very quickly, became very loud, heckled the speeches, announced her recent (six months ago) miscarriage to the room and then coralled me for nearly an on the balcony while she cried and told me how awful her life was.
I just found the whole thing quite funny (well, not the crying) and it makes for an interesting story, so if she was trying to ruin things it didn't work.
Anyway, that's my Terrible Wedding Behaviour story, I know you lot have some corkers, so spill.