Umm... Have your brother get her a bike or trike or whatever - and turn the damn tv off. Take her to a park with a sandbox or some swings. Give the kid something else to do or be interested in - rather than letting them figure out what they "want" to get into.

Kids need firm rules, boundaries, and limitations - no different than dogs or any other pack mammals. If she wants her Princess stuff - than it should be earned first, the amount of time and manner it's played with controlled, and she needs to respect the limits when it's time to put it away. If those things do not happen then no Princess playtime... period.

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