So i'm going to have a 2 year old and a new born and i am really not keen on getting a double pram. Basically i want to carry the newborn for as long as possible, probably up to 6 months due to my bad back, so in that period DS could still use the stroller if he needs. He's already a pretty good walker though... so i'm wondering by the time he's 2.5 would he be able to handle short walking trips? We currently use a backpack harness which he loves and it keeps him from running away.