This applies to all kids. As a child when we went to my cousin’s house (my late grandmother’s late sister’s late daughter) for Xmas Eve. She had really, really great food and fantastic cook and she was a strong believer if a recipe called for butter you sure as heck out in butter not substitute.
Anyways we would go there and my mother would say “give her a hug”. I really did like her but really felt nervous and awkward hugging. My grandmother would chime in “give her a kiss n the cheek.” along with the hug when we left. I so hated that.
My mother and late grandmother hugged her husband and her when we got there and left.
Neither my cousin nor her husband minded. Actually he always got up off his chair to hug them. He held court so to speak from the chair. He was not disabled he just believed his seat was his throne and rarely moved.
I suspect this hugging business was suppose to teach me something. Not sure what. Gratitude maybe? But that’s what “thank you” is for. I suspect parents want their kids to hug relatives for some unknown lesson. Just say “thank you” or a “thank you note” for invitation..