So I have a seventeen month old little girl. She is pretty well behaved most of the time but for the last few months she has gotten this habit of smacking me every time I pick her up. Now she isn't hitting me hard or because she is upset. It is just a constant patting/smacking in the shoulder. she usually only starts if someone else approaches me while I have her in my arms and they try to interact with her. I have tried to look up why she does this but everything I find on hitting is how to stop them from doing it, not why it is that she does this. and it doesn't matter what I do to try and stop her she will just keep doing it. I need some advice on why maybe she does this.