Sleeping
Sometimes I wake up in the morning not knowing who will be in bed with me. I sleep like the dead and therefore usually have no idea if a kid has decided to wake up in the middle of the night and scream until he/she is brought into our bed or if my wife has had enough of the kids and decided to sleep on the couch. Considering I'm as big as my wife and two kids combined and sleep in the fetal position my quality of sleep doesn't usually suffer much. If anything it might improve since the kids usually want to squish over to mommy's side which leaves me with most of the bed (otherwise my wife sleeps diagonally).
My daughter is the worst of the sleepers. She sleeps horizontally moves a lot and grinds her teeth.
My son is much better at sleeping with people. He cuddles with mommy and doesn't mind if I push him out of the way to make space.
Night to remember
A few years ago when my daughter was one and a bit she decided she was going to cry her head off instead of sleeping. At first we decided to let her cry herself to sleep. After crying for a hour or so we decided to rock her to sleep, after another hour of crying/screaming we brought her downstairs and turned on the lights. After another hour of holding and rocking and singing we put her back in her bed and left her. After all, how long can a child cry (considering there didn't seem to be anything physically wrong with her). At about 3 AM she decided that she had enough and went to sleep. I realized then that I was in trouble. If she is stubborn enough to cry and scream for 5 plus hours in the middle of the night through sheer stubbornness then teenage land should be tons of fun.
There are other nights I could write about involving vomit and such but nothing affects a parent more than hearing their child cry and not being able to do anything about it. Everyone should be happy to know that there is a happy ending though. Currently the kids go to bed on time every night with no crying:)