Congratulations on the forthcoming new babies x i would just keep the things you have , there have been many a time when my GC were little and have been at my house and there has been the need for clean clothes and something spilt on their clothes or some other reason , or when they are older a change of clothes needed to be out in garden, its amazing also what parents sometimes forget when they come for a visit with little ones, thankfully my daughter has never told me not to give children second hand clothes or toys ,i always make sure they are clean ,