ds2 is 2.7 and is.....challenging 
He is a lovely boy, affectionate and funny but VERY strong willed.
His brother (my ds1) was potty trained in a day at 2.10 and only ever had accidents when we forgot to get him to go to the loo before naps/journeys etc, despite him having significant developmental delay as a baby.
Ds2 has been the opposite...ahead in all his milestones, gross motor skills etc BUT would quite happily sit in a dirty nappy ALL DAY.
He doesnt tell us when he poos and, if we dont see him do it or smell it, he just sits in it...then he gets a sore bottom. (I do check him regularly btw)
He is supposed to start nursery for 2/3 mornings per week in September and I was thinking that I would try to potty train in the summer hols (after our holiday abroad) but I am getting increasingly worried that he just has NO interest at all in even sitting on the potty!
The potty has been upstairs in the bathroom for months now and he just uses it as a step! He did sit on it (its one of those chair ones with the removeable potty bit) a couple of days ago but tbh it seemed a bit small for him...he is quite a sturdy boy
So, what sort of potty suits sturdy children - or should I just get some of those padded seat thingies you put on the loo seat???
sigh...it was so easy with ds1 (the only thing that ever was, frankly!!) and I really would like him to be potty trained by the time he starts nursery.......