Why don't you see how it goes breast feeding the new baby - as Mamyalynne says you will still have to sterilise the bottles, and find the time to express, etc. I managed to breast feed twins, take my 7 year back and fore to school, take my 4 year to nursery every morning and pick him at lunchtime and look after my 2 year old (OK - I maybe over did it a bit as I got Glandular Fever when they were 3 months old!). I'm sure everything will work out ok whatever you decide to do. Good luck.