I know it's expensive, but personally I would buy one that is rear facing until 12 kgs. It is SO much safer. If you have any doubts, check out the video that Gigi is referring to - if you do a search on BB you will find the link in at least one thread.
DS2 is small for his age and was nearly 2 when we turned him.
If it were me, I'd pay the money to get a car seat that allows Jaz to remain rear facing for as long as she can. The you tube video is scarily compelling, so if Shel doesn't get it, just show it to her, so that she can see that it's not just BB chatter. Admittedly, it's much more fun when they're facing forward, cos it's easier to see them & talk to them, but at least 12 months in a rear facing chair is a good start, and if they've never been forward facing, they really don't know any different. I know that some of the better baby shops down here are certainly recommending 12 months as a minimum, which is a really good thing.
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