Great at Home, Hysterical in Public?

Has she every been in the care of someone else or around other people/kids on a regular basis? Such as preschool, daycare, play group, etc.?

Okay - red flag went up with the "flicks her hands around" this was one of the flags for my son regarding screening for neurologial issues such as being on the spectrum. I remember it seeming odd but it was one of them. For us, turns out he has ADHD. She could be TERRIBLY overstimulated by the changes, the transisitons could be difficult and no one is respecting or knows of her needs in this regard. If I were you I would talk to my sister about evaluations OR at least ask her to talk to the pedi about this ... honestly I think there is something more going on and I think the RIGHT kind of REAL HELP can do wonders.

Well, as others post, this could be a condition that needs evaluation, but it also could be as simple as lack of exposure to anything much outside home. Before rushing to assume it's autism or ADHD, I'd have her slowly and gradually exposed to new people -- first through having more visitors at the home; then having her babysat at home (do they do this at all? Or is she with a parent and at her own home almost all the time, and maybe has never been babysat even for two hours at a time?); then gradually taking her out. If they are taking her from the calm and relative isolation (just the three of them) of home, it is too much, too fast to take her, for instance, straight into a large family gathering with a lot of people, or a local festival with huge crowds, or even a kids' event with bunches of other kids. I would get her out to a quiet place like one end of an isolated park (not around other kids and families) and arrange for ONE grandparent to meet the family there--just one, and just for a fairly short time like half an hour at first. Very gradual buildup of exposure to people, in other words.

She may feel like she has zero control if she is anywhere other than at home with mom and dad -- like she has no idea what to expect and no way to control her surroundings or herself. This would be terrifying to her so what you see may be pure fear.

I would get her a full physical and mention this to her doctor and ask if the doctor thinks she needs to be evaluated, but if she has had little to no exposure to other people outside home, of course she is unable to handle it.

Has she ever:

Been in preschool? Been left in a church nursery for a short time while the parents attended a church event? Had other kids her age over at her own house to play? And so on. This is stuff the parents have to answer -- not you.

One thing that concerns me is you say that "in pictures she is always all smiles" and that you feel like she is happy "in my SIL's Facebook posts." It's easy to get a photo of the one happy moment and post it for the world to see. For all you truly know, the girl could be just as agitated and anxious at home -- you can't tell by looking at Facebook. I would talk to mom and dad (both, not just one) and say that you see such a happy and relaxed child on FB but not in groups outside home, and tell them you're concerned. They may already be getting her evaluated.

Barring medical issues (hand flicking? Have that checked for sure), sounds like she's allowed to act that way. Two of mine preferred not to be around others at that age, and tried some fits about it. It wasn't allowed. They didn't have to go give hugs and kisses, but they were not allowed to be rude or throw fits either. Sounds like a discipline thing to me. And it's one of those tricky ones because it really seems like the child needs affection and patience for it, but in reality, if she wasn't allowed to act that way, she'd be on her way to having fun in any setting a lot faster.

For example, my friend and I parent in totally opposite styles, our youngest daughters are the same age. Mine was very anxious about "blending" but I kept the rule firm on not clinging, not crying, etc. My friend would let her daughter cling to her lap and whimper for an entire three hour gathering. My daughter got over it almost instantly and is very friendly now. Her daughter still plays "scared" whenever she's not the center of attention. LOTS of kids pull the terrified routine (I don't mean they aren't genuinely shy or nervous, but they can be taught to behave well nonetheless) with people other than mom or dad. It's only rarely medical.

All kids are different, but if she doesn't have a real disorder, her parents can change this. But again, hand flicking may be something weird.

I had the same thoughts as Kristina. Handwaving is something our friends' daughter does when she is excited or overwhelmed. It's like she has this energy that needs to come out her fingertips. She has Autism. I think that if your niece does well in stable, predictable, controlled environments and only reacts like this if things are out of order, then something else is going on and she should be evaluated. It may not be Autism at all, but I would encourage her parents to look further than simple anxiety. My ILs tend toward being agoraphobic and crowds could encourage nervous behaviors in my niece when she was younger.

Sounds like my husband :)

Before addressing the issue of hand flapping I would suggest taking her to have her eyes and hearing checked.......simple, easy, and non evasive. Then, if the parents are willing, a developmental pediatrician might be in order. The things that she does in public might be exacerbated BECAUSE she is in public. She might be doing the same things at home but much milder and so it does not draw the parents attention. ALWAYS better to error on the side of caution.

Are you sure she's always happy at home? It sounds like you only see her at home in pictures. Anyone can give that impression with just photos.

I think a lot of kids go through this at 3 years old. She will probably outgrow it.

Although I will say that my #3 GD didn't like to be touched by anyone other than her mom and now that she's 12, it hasn't changed! I don't think she's ever kissed me, even on the cheek. I don't push it; I just give her a brief hug.

She seems to not like, things that are not of routine things.
Meaning, anything that is outside of her regular routines and people she is usually around routinely.... it tweaks her.
The common denominator being: that when she is around people she does NOT know... she does this. Even if/when her relatives are around at the same time.

Or, is it that perhaps, she only has these issues... when around your sister-in-laws and their family?
I say this because, you said that she is different around your sister-in-law/her family, and when you see her in person and when around her parents and you.
So the point being: is the girl, different with a certain family, versus her parent's family?
If so, then how is the girl being treated, by that family?

She sounds very anxious. I was a very shy child and would hide behind my parents or just go to another room where no one was when I was young. My daughter is the same. She doesn't go into hysterics but she won't look at someone etc. Maybe she simply has high anxiety and really just needs to have everyone wait for her to approach them - give her a warm up time.

My thought is -- don't worry about it.

If you compared my daughter at 3, who cried all day when I tried to leave her at preschool, and then whispered to the teacher when she was giving her "sharing" speech at 4 years old, to the incredibly competent 19 year old who is not afraid of anything and basically excels at life, you wouldn't think it was the same person.

Don't be sad, she's only three.

Others are concerned about the hand-flicking. I guess depending upon the nature of this hand-flicking, it could be of some concern, but a 3 year old waving her hands a few times doesn't necessarily mean anything. If you mean that she goes into bouts of relentless hand-flapping, then yes, that could be of concern. But I didn't get the sense that that is what is going on.