Dear Cheryl, I agree with the other tom that You should have a protective plastic sheet underneath to protect the bed wether you use pullups is up to you as a mother !if the children have been constant bed wetters since birth and nothing is physically wrong with them then it is just a matter of waiting as the majority of children grow out of bed wetting! I suggest you look at the pro's and cons of useing pullups if your twins are happy with this set up then fine but if they are rebelling against having pullups on then to coin a phraise you can lead a horse to water but you cannot make it drink!. also My personal view is prolonged wearing of nappies/pullups can lead to problems in later life just look on the main wetbuster board and read what it says about the wearing of nappies ! but as I said the decition is yours! .best wishes Tom.uk