My daughter will be just over a year old when we have our second daughter. I was debating just using my old college backpack (it's fairly large, lots of pockets) as a diaper bag but I know they also make backpack diaper bags and am also thinking about buying one of those. Should I have two diaper bags? I was thinking in case one baby is going somewhere (like staying with grandparents which my oldest will be doing when we go to the hospital to have the baby) it would be a good idea to have two on hand.