Forget coffee, try a cradle

So I read somewhere that babies sleep 16-18 hours a day. Is there an unwritten rule somewhere that says that none of them can be at night? I love Kerrigan to pieces but no matter how hard I try, I end up getting frustrated when she gets up 50 times. Last night I rocked her for 45 minutes and had her good and asleep and as soon as I laid her down in her cradle, WAAAAAA!!!! She seems to be able to sleep just about anywhere but there. Just the other day we were trying to feed her and couldn't get her awake enough and my wife jokingly suggesting laying her in her cradle for a while. We didn't try it but I still bet that it would have worked. :)