Do you sterlise sippy cups?

[HeidiKat]

My DD is almost 5 months and I am about to start weaning and also want to start giving her a drink of cooled boiled water in a cup with handles to get her used to holding and drinking on her own. I won't be giving milk in a cup until she is used to it as I suspect that more of it will go down her top than in her mouth and don't want to waste milk. If I am only using the cup for water is it really necessary to sterlise it even though she is less than 6 months old. I ask because I have just tried to sterilise one in the microwave steriliser and it wasn't microwave safe and started to melt .

I do not think I did, once they are crawling all sorts of crap goes in their mouths. Plus, if it only being used for water, its not like milk which can turn nasty

I wouldn't. I assume she puts toys in her mouth that aren't sterilised? It's not any different. Would if milk was going in it though - like Praline said

Thanks for the advice, she is at the stage where she puts everything in her mouth anyway so I will try to worry a bit less and just wash her cups with the rest of the washing up.