katkins - will she wee on the potty WHILE she is wearing her undies? it'd be a start.

then you could cut a hole in it. i'd try to tt both girls at once. jessica I see is almost 2. definitely not too early. doing them together could create some healthy kind of competition! (BUT, so that you don't go insane - I wouldn't take jessica out of nappies yet - just encourage her to use the potty as often as possible - eventually she will do most of them in there and then you can drop the nappies- but that could be weeks/months away. if you don't stress about it, it won't matter how long it takes - starting earlier.)