Hi, my DD is 12 weeks old and she smiles and coos and babbles all the time every day she’s a really happy baby but she hasn’t laughed yet, I have tried literally everything and nothing has worked, she doesn’t seem to be on the way to laughing at all and I don’t know what to do! Everyone else’s baby’s have laughed by now and my DD just hasn’t at all not even a hint of a laugh! When did everyone else’s baby’s start laughing? Thanks :)