My almost 22 month old daughter, who is a very happy and fun child most of the time, has started an odd behavior when she is around other children—mostly those who are close in age to her. As they approach her, whether it be to see what she’s doing or to go down the slide at the playground, she will “squeal” at’s kind of a “mine” type of reaction but instead of saying that, it’s like she’s marking her territory/personal space. I’ve tried everything to distract her and redirect her but it hardly works. I have noticed that she will eventually stop but it takes some time. She’s not overally shy, warms up within a few minutes around others and is usually social around others up until the last few weeks.
Is this normal? Should I be concerned? I do stay home with her but I’m told by her Sunday school teachers and the occasional times others watch her, that she’s never reacted in this manner.
Help? Suggestions? Shall this to pass??
She’s developmentally on track and has hit all milestones thus far.

Pic for attention 😋