What is the go with a swim nappy? How many do you need? Is it a case of having to change them if they are dirty and putting a new one on because I imagine it just runs straight through? I am looking at a Happy Babe one but before I buy one want to know if they work. I imagine bubs poo to be pretty runny, how is it really contained in there? I hear people take their babies to swimming lessons pretty young these days and dh and I also want to take baby swimming, I guess you need to have a swim napppy on then?