Dear Monnie, When our DS was born he was only a littley 6lb11 and the size 0000 were quite big on him. He also was vomited alot as he was an emergency CS so had lots of yucky mucous in his tummy so we had to change him 3 or more times a day. So having learnt that lesson this time we are taking lots of clothes enough for 2 or 3 changes a day. Yes wash all the baby clothes before you use them in a mild non enzyme detergent and yes our baby always had on a singlet. The best things are the Bonds jumpsuits. We took about 6 or 8 of them and then about 10 singlets. Keep in mind that babys do grow really fast and if your baby is a little bit bigger say 8lb or over then the 0000 might be too small. We also took about 5 or 6 baby wraps too. Even though the hospital we had our DS at provided clothes and baby wraps many do not and they don't take up much space so pack extra and then if you have a bub that vomits you'll have plenty of spares. Good luck with you bub.