Re: Baby essentials, shopping, and registries
strollers usually go by weight, not age. most of them go up to anywhere between 45-55 lbs, i believe.
car seats you have to upgrade- infants have to be in rear-facing seats until they're 6 months old, i believe, and then they move into forward-facing seats. these too are determined with the height and the weight of the baby but i'm not sure how frequently you would upgrade your car seat.
also, since you're coming in from abroad, wait and buy your stroller/car seat here to make sure they pass canadian safety standards. these do vary from us standards in some aspects and also your warranty might not be applicable between us and canada.
if you buy a travel system, the frame of the stroller can accommodate a car seat, bassinet and the stroller sea; so this makes them more versatile and the theory is you don't have to disturb your sleeping baby if you need to move them from car to stroller and vice versa.