ghost hanging around my stepdaughter!!

Leigh
Okay, so I believe in ghosts. Although I have never seen one! My two brothers and my mother see things. My older brother is a medium. So I live in a bungalow in the middle of nowhere, trees and cows are all that we can see! I figured out there were spirits in the house about 4 months ago when my step daughter started crying for no reason and pointed into the corner of our kitchen and said there was a monster there! Since then though she hasn't been too concerned and whatever spirit is in the house is nice and he plays with her! She said he's an old postman, and she's always playing in her room with him! She waves out the window to him and says he's a nice man, so I haven't been concerned as I know some spirits just want the company! However recently my brother came down to my town to visit, (he didn't come to the house) and my partner and I were speaking about the spirits in our house. They have been doing small things like moving objects and things like that but we haven't been worried. When We came home that evening my uggs where off the shoe rack in the middle of the room! They always seem to do this, but I laughed and thought it was them almost saying 'oh you were talking about us, so just letting you know we're here'
However since speaking to my brother weirder things are happening, maybe it's Because they know we acknowledge them?! But my partner heard knocking on the front door late at night, and in the last two days we have both heard crying.. but this crying is the exact same as our children's cries! Last night I heard sobbing crying, and it was my step daughters crying so I got up to check on her and she was fast asleep and there wasn't a sound out of her! Then today my partner was in the bathroom and said he heard crying as if it was coming from the living room! He said it sounded exactly like our newborns crying but he was in the bedroom and when he went to check on him and he was fast asleep! Crazy right... and that's not the worst of it! 
My stepdaughter has started saying there's a man outside her window at night time! I've heard about this man before because he use to hang outside of both my brothers windows when they were my step daughters age (she's nearly 3) I suppose what I'm trying to find out is has these kind of things happened to anyone else? And should I just tell my stepdaughter to start ignoring these spirits...? I know children are susceptible to spirits but i don't want her seeing things that scare her and they're obviously coming to the house because she entertains them?