We considered holding back Brendan from Kindy (4yo) but decided to go ahead with it anyway. Brendan has a range of issues, developmentally, socially, sensory and some medical things too. Holding him back seemed like a good idea, because I don't think he is ready. But at the end of the day he has to go someday and I figured that if we enrolled and he didn't cope well we would just pull him out for another year.