11 week old no smiles

[NobbyD]

My 11 week old ds2 still doesn't smile. Done lots of reading up about it and it seems that 12 weeks is the cut off in that he must smile by then.

My question is what does it mean if he doesn't smile by next week??

Seeing paediatrician this week anyway for follow up as he v small baby (born full term 4lb 10 but hasn't gained much weight since) and he'll be checking for smiles

Should I worry?

I think you are right to be concerned, but it's good that a paediatrician can give him a check over and tell you whether there is cause for concern.