I do know that the
Sunshine Kids Radian fits newborns really well and is a very narrow
convertible so fitting 3 across shouldn't be a problem. It will RF to 35lbs and then
FF to 65lbs (the one in Canada will only go to 65lbs..they have an 80lbs version in the states). These seats are also good for 8 years..so they could very well be the only carseats you purchase for your children. I would definitely get to a Zeller's, Canadian tire, Sears, toys r us, etc and see about trying some out. Also, contact a CRST (child restraint safety techinican) in your area to help assist you with carseat install. They may also be able to help configure/puzzle some seats in your vehicle to confirm a good fit for everyone.