is there a super narrow seat other than a radian?

[mamasthree]

Our radian does not fit at all RF on the bench seat 3rd row of our suburban--it is just crazy reclined, the seat of the car is very flat.  I would really like to continue RF my nearly 2 year old, but need to move her to the back seat.  It has to go in the middle...no room behind the captain chairs in the 2nd row.  UGH!  I have a marathon (it's what she uses now), but the radian FF for my 4 year old doesn't fit next to it in the back.  Plus, the Marathon's base covers the other seat belt buckles (they are forward of the seat bight).

Suggestions?  My brain hurts and I just want 2 seats that will work back there so my older girls can have the middle seats (they are 5' and 5'4" at 10 and 12, so the back seat is pretty tight for them, not to mention their heads are above the highest headrest positions).  But right now the only thing that seems to work is 2 FF seats back there.  And that's not even good because there is only one tether anchor! 

Maybe I should buy a minivan--or a new third row seat for my Suburban (which I love except for the car seat thing!!) 

[DahliaRW]

The complete air is decently narrow (I think 1 1/2 - 2" wider than the radian) and has a nice tall shell.  The concorro and scenera are narrow too, but have shorter shells and a 2yo might be close to outgrowing them rfing.  They carry the CA and Scenera at BRU, so you might be able to go try it with the radian and see what works.

With a convertible and an older child, you can install as upright as 30 degrees, which might help it fit on the side and not the middle.