Hmmm - I'm asking because the other day I had to give her an unsterilised bottle (car broke down in the middle of nowhere) and luckily we had washed it out well but it wasn't sterile. She will take her milk cold and she seemed fine after! I mean, a few times if her dummy has fallen I just give it a wee rinse (or a wee sook if icant rinse it) and give her it back. She never been I'll from it, was just wondering about bottles too! I'll prob keep sterilising until a year or until she stops bottles I think x