He does them type of gas smiles quite often and in his sleep. But he’s not socially smiled where he’s awake and reacting to seeing me for example. He said they can smile anytime from 6 weeks which he is now. Usually from 6-8
Mine is almost 7 weeks and only just did it, so dont worry, babies take their own times
Mine is just under 2 weeks old and was fussy all day the other day. I think it was gas related but occasionally he would smile. Idk if this situation counts but I think it just depends on what’s going on with your child at a given time. Did you check with his pediatrician to see if what is going on is something to be concerned with or just to monitor?