Kids Never Change, They Just Grow Up

We have unique relationships with each of our children. Husband and I communicate and interact differently with each. We know them pretty well and are rarely ever surprised by what they do. It's out of character behavior that worries us. Since childhood, their personalities and mannerisms have remained constant. I don't mean they are childish. They have matured and become wise, capable loving adults (and one teen). I mean personality traits haven't changed. Here's a little vignette on that  Kids Never Change, They Just Grow Up