Girls, we're 3.5 months old. The question is: how much should babies s…

Girls, we're 3.5 months old. The question is: how much should babies sleep during the day at this age? We just don't get much sleep! If they sleep during the day, then we have to constantly carry them in the stroller, I can't even sleep myself! When you carry them, they sleep for 15-30 minutes and that's it! How do your babies sleep? Is such a sleep normal like ours? What can help us fall asleep during the day well?