Complex sentence: When they became parents they were given a position of authority over their kids, but when their children begin to grow they tend to dislike the authority that the parents have even when the parents are only telling them what to do in order to help them.
Split into simpler sentences: When they became parents they were given a position of authority over their kids, but when the child begins to grow they tend to dislike the authority that the parents have. Even when the parents are only telling them what to do in order to help them.