Wife wakes up the baby constantly

My wife is brilliant, but she has this terrible habit of being an insufferable moron when she’s tired and right on the verge of sleep. She’s been pretty good the past couple months, but now that out daughter is 4 months old, my wife is getting worse.Example: tonight, she was lying in bed, right on the edge of sleep. I got the baby down in her crib (which is in our bedroom), when my wife suddenly says “lemme ask you a question. What was that game we played with the chairs and music and running around?” I responded “musical chairs?” She started singing Frere Jacques at the top of her lungs “No! It was the one with the chairs and this song!”Obviously the baby is awake at this point, screaming and crying. It takes another 30 minutes of cooing to get her down again.Episodes like this occur a few times a week.How do I delicately tell my wife that she’s a raging idiot at night and she needs to sleep elsewhere? via /r/Parenting http://bit.ly/2Beu4S9