I have a 4 1/2 year old girl who was open and friendly until about age 3, and has become increasingly standoffish. No major family changes, so I'm wondering if this is an ages/stages thing. Sometimes friends or family members want to hug her and she pulls away, refuses, or only hugs if they act like they don't want her to. These are completely harmless people who don't put off strange vibes, or anything like that. A related problem is people say things like, "Hello, dear, how are you?" and she stares at them and does not respond, or simply keeps walking like she has not heard, which is clearly not true (I think she is choosing not to hear, though I have no idea why). I have told her to respond to people's questions, because it is rude not to, and it hurts feelings. She's verbal and affectionate with me, and normally a smart, kind, little girl, and I have to say this behavior worries and aggravates me a little, to be honest. Thoughts?