DS2 is exactly two months today (born at 39+3). We have gotten a couple of social smiles from him, one on Christmas and one today. That's it. DD and DS1 were super smiley by nine weeks so of course I am worrying. His 2 month well visit is in a couple of days and I will bring it up then, but right now I am looking for any similar experience.
My sister's DD has ASD and global developmental delays so I am kind of googling myself into the rabbit hole