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In all likelihood, she's going through a phase and learning about social relationships. At 5, the world is a whole new place--bigger with more possibilities. The more intelligent the child, the harder and wider their explorations will be. She's testing behaviors to see what works...that's her job right now. She's learning to live in the world. Your job will be to set the limits and give her the information to work with - over and over and over again. It can be exhausting, but it will pass.
You're describing a child who is very aware of social connections and wants to be right there in them - nothing wrong with that. She just needs direction and re-direction. Give her verbal cues and don't be afraid to pull her in and out of situations for quick lessons....8 words or less and then let her back in. Do this repeatedly, and if she can't break out of a situation, pull her and redirect to another task.
It will take some work, but a girl like this will most likely need lots of social guidance by using verbal cues from you. At night, you can go over your point in a bit more detail, but not much..don't weigh her down- it won't do much more than the quick ones. Reading books about relationships helps girls like this- I just read one by Madonna about the English Roses that was good, but maybe a bit older for her. But if you look at that, you'll see the direction: it's stories that help girls understand how to negotiate relationships with kindness and understanding.
It's not about disrespecting adults, it's just that she has all this new power as a person and doesn't know how to handle it yet or where to use it. You can help her along by quickly intervening with guidance and quickly stepping back. Read her books, and model play with her using dolls and her brother. Narrate your "thoughts" and reasons why you're doing what you do. She'll hear you and it will sink in.
I doubt you're doing anything wrong...it sounds like you've got a social little girl who has just entered a new developmental phase.
My best to you.
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