My DS2 is 12months and he is the same - he just won't sit down. He doesn't seem to mind being in the bath though, but as long as he is standing! As soon as I gently force him down he'll burst into tears and try to climb out....so baths are usually rather quick for him - a quick sponge down. DS1 was the same....I still remember clearly going through that phase around the same age...constantly saying 'sit down' (and still go through phases every now and then with him too - though they only last a few days usually- he will be 3 in May).

You can put dye in the water to make it a coloured bath too, i think its just food dye. Get her to choose her fav colour. Does she have a fav toy or doll that can go in the bath?
I've been doing this since DS1 was about 18months....when once again we were struggling with bath time. I ask DS1 which colour he wants and it makes it more fun - though I know this probably won't help with you just yet (my DS1 didn't really understand colours til more 18months I think). But the colourful bath may help - we just use food colouring (doesn't stain the bath either).

I've also been meaning to go looking again for those bath crayons - to draw on the bath and wash away. Someone on BB suggested maybe Myers (I've looked almost everywhere else already...so hoping they'll have them). I remember having them as a kid - we had ones in the shape of a car....they were lots of fun.

I also do alot of singing and play music - I have alot of wiggle songs on my mobile - so this seems to help keep them happy too.

Also what about if you or your partner are in the bath with her?

Good luck...hopefully the phase will pass and then you'll have the issue of trying to get them out of the bath (pulling the plug helps there )