Rude/Attitude how do you deal with it?

[charlietherednosedpussy]

Twice tonight dd 8 has been what id call rude, or has done something to me she wouldnt dream of doing to anyone else.
Firstly after me telling her off for poking her sister she sort of made a Pah...whatever noise that came out as a spit IYKWIM and secondly I took her up a hot water bottle for bed and she totally ignored me/grunted at me for asking her to put her gameboy down to take the hotwater bottle.
First thing I made her sit on the bottom step for 5 mins, second thing I gave the hot water bottle to the dd who was laying down quietly not being rude and that of course made dd1 howl...although dp appeared 2 seconds later with another.
Anyway...how do you deal with it?

I spent all afternoon making an angel costume for a less than grateful angel (aged 6)! When DH came home I asked her if she wanted to try it on and show Daddy and she said no in a very "can't be arsed" tone!

I told her to go to her room and think about all the things I do for her that I needn't bother doing and to come down when she'd changed her attitude and showed some gratitude.

Off she stomped only to come back a few minutes later full of remorse and sorry mummy I love yous!