The game doesn't work properly when there is an infant in the household

My game keeps glitching and is unplayable since my baby turned into an infant! I have lots of of packs and expansions but I don't have any Mods. The characters freeze or refuse to carry out actions but time continues. I have noticed that it often happens when using the crib so I changed it to a different one. The game was playable for slightly longer before I had to save and reload. The infant has also got stuck to the adult on occasions. I love this family. I really hope it is fixable