My 4yo definitely precedes her poos with a round of farting (whilst denying that's what she needs to do or blaming the baby!). She potty trained at 2y9m and I was mystified by how she could manage to make it to the loo for wees but not poos. I'm afraid I can't remember what we did but I don't believe it was anything more special than having a lot of patience and employing smarties as bribes/rewards. All I can say is hang in there and take comfort from the fact that they all get there eventually!
DD (2.5yrs) has been daytime dry (& not very wet overnight) for 2wks (woo-hoo!), however, poo is a bit of a different story, in the last 3 days she has done 2 x poos in the potty, but otherwise all are in her knickers. (Interestingly the 2x potty poo's were done when she was alone).
Anyhoo, she doesn't show any signs when she has a poo - no straining/stopping activity/hiding, the only thing I think is a sign is that she has v smelly farts - on smelling I try & get her onto the potty.
However, DH doesn't believe is is a sign & says that he often farts without wanting to poo & so DD does too - my understanding is that in toddlers unlike adults it IS a sign & it's the only sign we seem to get.
Today DD had a few v smelly farts in the hour or so following lunch, encouraged her to use the potty but to no avail, few hours later she poos in her knickers & then in the bath
DH reckons this shows the farts meant nothing, I think they were a sign but that she was holding on - who's right & is there any evidence (potty training tips or similar) to prove this?!