My son is 18 months old and still won't use one. He would if I held it up for him, but if he held it himself, he'd either chew on it or try sucking it up like a straw. So we've just been using the straw cups instead, and it's much less hassle. They make spill-proof ones if you're worried about that, or I like the Take 'n' Toss ones; it's no problem for them to chew on those straws, you don't have to take apart a whole bunch of pieces to wash, and they actually don't leak out of the straw hole (of course if they hold the cup upside down it will come out of the actual straw, but not where the straw goes into the lid, so if it just gets knocked over on the table, it's probably not going to spill).
at 12:46 PM on Jan. 4, 2009