I'm Canadian on the technicality of being born there and holding citizenship, but I've never lived there, and don't have any local knowledge. I do have a few relatives that have local knowledge of BC, if not of Vancouver, though.
Aha, thanks all! In short, we are looking at travelling with a 3.5 year old and a 6 month old towards the end of March. Questions we have really are how easy is Vancouver as a place to get around with young children, what the weather is like that time of year and specifically we have read a bit about Bowen island but all accommodation there seems ludicrously cheap for that time of year - is there something we are missing?!