Family did a surprise baby shower, so thankful. I want to return my car seat because my in-laws got me one with a…

Family did a surprise baby shower, so thankful. I want to return my car seat because my in-laws got me one with a stroller! Can I return mine back to baby r us if I don't have the receipt? & if it was on sale? I thought I saved it just in case but I guess not. If only I knew I wouldn't of bought it.