I've been very kindly lent a baby gym mat - padded, bright colours, etc that they lie on and play with the toys hanging overhead. It's been in a loft for at least 3 years and previously to that was secondhand. It's in really good condition but I'd like to freshen it up a bit. It won't fit in washing machine so do you think it would be ok if I put it in the bath? Should I just use soapy water or put some milton in there as well? Will the milton bleach the colours? 