although the 3 door would be fine life would def be easier with a 5 door.
i have a 5dr with a 7 yr old and a 3 yr old and im imagining pouring rain with a nasty wind whilst the front seat is forward and door wide open while you are fastenning his / her seat belt and then giving them whatever attention they need before you actually get in the car yourself.
i still remember the days having this problem esp if it is a busy road with one foot outside the car and one foot in the back whilst frantically trying to get the little ones secure in their seats and giving them things like teddies etc before someone came along and took my large drivers door off along with my leg.
at least with the 5dr the door is a lot smaller and lighter.
the joys of adapting for our little ones lol