Sienna Miller's father has threatened to kill Jude Law if he cheats on the Alfie actress again.

Miller split from Law in July (05) when he confessed to having an affair with his children's nanny in March (05) - but they rekindled their romance last month (NOV05) and are now working on building a happy future together.

But ED MILLER has warned the Cold Mountain actor to treat his daughter properly, or else he will face the wrath of her father.

Miller says, "He did a lot of hard work, trying to figure out who he was.

"And I told him if he did anything like this again, I'd kill him."