This very famous actor had an illegitimate child many years ago.
While he has gotten to the point that he now openly acknowledges and spends time with that child, his other children are not nearly as accepting.
They have all met their half-sibling… but they definitely see them as an outsider and an interloper.
They have also made it very clear that they do not want the half-sibling invited to any family’s events (e.g. birthdays, weddings, graduations).