Social smiling

I’m a bit worried as my LO is 8 weeks old tomorrow and still hasn’t done a proper social smile. I see people on here talking about their 2-3 week olds smiling but I’m not sure if they are talking about the more reflexive wind/gas smiles or the falling asleep smiles or if they are in fact talking about proper social smiles (looking into your eyes and smiling in response to your smiles). How old was your LO when they first did a proper social smile and when did they start doing it on a frequent basis?