Catherine Zeta Jones has shared a card sent to her by father-in-law Kirk Douglas on her wedding anniversary.

The actress and her husband Michael Douglas are celebrating their 19th anniversary.

Zeta Jones shared a photo on Instagram of her letter from Douglas Snr, who is 102.

It said: “Dear Michael and Catherine, Happy anniversary!

“Michael, you have learned a very important lesson, to stay married you must obey your wife!

“Keep practicing what I do with my wife.”

Kirk Douglas
Kirk Douglas (Myung Jung Kim/PA)

Zeta Jones, 50, also shared an old photo of her and Michael on the dancefloor.

She wrote: “Dancing in to our 20th year!

“Happy Anniversary my love. Such a beautiful letter from my father in law. I am touched.”

Her husband, 75, posted a black and white shot of them hugging.

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Happy Anniversary my ❤️ #19years

A post shared by Michael Douglas (@michaelkirkdouglas) on

The star couple tied the knot at the Plaza in New York in 2000.

Zeta Jones and Douglas are parents to son Dylan and daughter Carys.