Star siblings Kate and Oliver Hudson are considered "dead" to their father and actor Bill Hudson.
The 65-year-old actor, who has three other children, has requested Kate and Oliver, who he fathered with actress Goldie Hawn, to stop using the surname -- Hudson, as he doesn't consider them to be his children after their hurtful posts on micro-blogging site Twitter on Father's Day, on June 21.
Along with a photograph of Bill with the two siblings as young children, Oliver had posted to his sister: "Happy abandonment day...".
"I say to them now, 'I set you free'. I had five birth children but I now consider myself a father of three. I no longer recognise Oliver and Kate as my own," Bill told dailymail.co.uk.
"I would ask them to stop using the Hudson name. They are no longer a part of my life. Oliver's Instagram post was a malicious, vicious, premeditated attack. He is dead to me now. As is Kate. I am mourning their loss even though they are still walking this earth," he said.