Mine were all different, #1- one week late (induced), #2- nine days early, and #3- right on time!
All were extremely close in weight, too, (7.15, 7.12, and 8.1) so that didn't seem to make a difference.
It is hard to guess! Although, for some people, I guess if there is a pattern, you could reasonably expect it to continue...
my three were the all the same too...roughly 2 weeks late and just escaped induction by a matter of hours. weights differed though; 7lb 6 ozs, 6lb 9 1/2 and 8 lbs 13 ozs.
All mine have come at 42/3 wks by way of being induced, so for me all have been the same and I can't see it being any different this time, although I hope I can go into labour naturally as I don't know what it is like and it would be nice to know!!