B.F.
I put the baby behind the driver's seat and my oldest behind the passenger's seat just becuse it mad the carpool line at school easier and I didn't have to get out and walk my oldest around the car. They are now 8 and almost 4 and still sit in the same places. It is also easier because Emma is still in a 5 point harness (and probably will be until she starts Kindergarten because she is so little) so I am able to buckle her in right before I get in.