SO ready to scoop up my cranky 3 month old and leave the in-laws' house...

My father in law is a pediatrician and has been pathologizing every wimper and sour face my kid is making. She's EBF, but is looking about five/six months old at three months. He insists she's crying because she's hungry and that I should start feeding her cereal already because she's been nursing every hour or so. How about she's having a growth spurt, teething like crazy, having trouble sleeping in an unfamiliar place, and off her schedule because of jetlag?! Grrrrrr.... I'm not totally dismissing the idea that's she's ready for cereal, but he is NOT my pediatrician, and I'd rather hear it from her first. (I should add that the week before we made this trip, she was sleeping all the way through the night, nursing every 2-3 hours during the day, and pretty darn happy.) He's being really pushy and controlling, and I am SO glad our flight leaves tomorrow.