Secret Split: Robert De Niro Filed For Divorce From Wife Grace Hightower In 1999

Robert De Niro divorced his wife, Grace Hightower — but managed to hide the proceedings from Hollywood, sources revealed to RadarOnline.com.

Amazingly, the Raging Bull icon, 75, and Grace, 63, put their differences in the past — and even publicly renewed their wedding vows — while convincing the world they never legally divorced after De Niro filed his court papers in 1999.

Now, the Oscar winner’s lawyer insists the couple “were divorced years ago” — even though RadarOnline.com can find no public records indicating the split was finalized after the 1999 filing.

“If they did, in fact, divorce, it will be one of the biggest secrets ever in Hollywood history,” said a source. “Normally, you just can’t keep such a high-profile split quiet.”

But prominent New York divorce attorney Julie Hyman noted you could split on the down-low by agreeing to resolve the marriage in uncontested proceedings after “working things out behind closed doors” and “sealing the files.”

The publicity-shy couple wed in June 1997. Hightower gave birth to their son Elliot in March 1998.

But things quickly turned rocky — and De Niro filed for divorce. The fallout continued into 2001 as the two waged a bitter custody battle over Elliot.

But in 2004 the couple, who are worth an estimated $500 million, renewed their wedding vows during a star-studded bash at De Niro’s farm near New York’s Catskill Mountains. Their daughter Helen was born by surrogate in December 2011.

Now Hightower and De Niro are said to be happier than ever!

“It’s well known their marriage has had its share of low points, but they’ve seemed to overcome them all,” says an insider. “They’ve been together 20 years — and that’s a lifetime by Hollywood standards!”

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