C.P.
I have a 2 1/2 year old and a 5 month old and we just bought the phil and ted double stroller. It's a little pricey, I think we paid around $6-700, but it is so worth it. It can do so many different positions. It can be a single stroller, with baby laying flat on his or her back, or in the car seat, then you can also have the carrier on top and toddler on bottom. Or toddler can sit on top and baby lay down underneath. Then when baby gets old enough, they can both sit (top to bottom, not side to side). I have never had a problem fitting through doors or fitting down isles. It is as slender as a single stroller. It also has outdoor tires, so you can use it indoors and outdoors. We LOVE ours!!! I hope I helped.