Because they are children and are not yet socialized.
Answer.
Children learn from their parents. The parents are setting the role model example for their kids. When my son was growing, I constantly...
because they live together while they are growing up, and they find out each others pet peeves and the annoying things each other do. they are also not embarrassed around each other, so they do...
A sibling is referred to only between brothers and sisters. The only time a parent would use the word sibling is to refer to their brothers and sisters. ::MizzCorleone