I really think a Snuggli or BabyBjorn type carrier(of course not the expensive ones) would work because the "doll" would be strapped right of the front of the little girl. The doll would not have to be removed for rides.
Similar to this...
http://www.amazon.com/exec/obidos/tg/detail/-/B000059XOD/002-3687465-2540819?v=glance
Hope that helps.
Similar to this...
http://www.amazon.com/exec/obidos/tg/detail/-/B000059XOD/002-3687465-2540819?v=glance
Hope that helps.