I had 4 in 4 years (and 2 months) so all mine were quite close, but I only got my first double pram last year because it was easier for school drop off/pick up.

At the start of last year I had a 3 year old, 2 year old and 10 month old, so the two oldest went in the pram, and the baby went in a carrier on my back.

Having said that, I used it for last year, and now don't use it unless we are going walking and its a fair distance and I don't think the girls will walk it all. All the kids walk for school drop off/pick ups.