Please!
DD is 11.5mo and is still rear facing, but, um, in the same car seat she came home in - Stokke Izi Sleep - and she's getting somewhat cramped now. She's tall and slim - she's just under 9kg so still well within the weight limit of the seat.
A problem is that the Izi Sleep is so massive, if anyone is (I am) sat in front of her, their (my) knees are rammed into the dashboard which is uncomfortable for anything more than about 20 minutes so don't really want a bigger seat, which I assume I need as she is long. I don't know! I am utterly clueless when it comes to seats :(