A NASTY family feud has erupt­ed over PAUL NEWMAN’s multi-billion dollar estate!

With the late actor’s wid­ow, Oscar winner Joanne Woodward, struggling with Alzheimer’s disease, his children are considering taking legal action to get a larger chunk of the family fortune, The ENQUIRER has learned.

“Paul left the bulk of his estate to Joanne and his charities,” a close fam­ily friend told The ENQUIRER.

Prior to his death, he gifted each of his five daughters with an inheritance of $5 million, but “he felt the girls were all successful and didn’t have to rely on fam­ily money.

“But the girls are now suddenly sensitive to how much Joanne is worth, and they’re concerned that she may cut them out of her estate entirely and leave every dime to charity.”

The 82-year-old actress – best known for her Academy Award-winning turn in the 1957 classic “The Three Faces of Eve” – was married to Newman for 50 years before he succumbed to lung can­cer at age 83 in September 2008. She and the blue-eyed screen legend had three daughters – Nell, 53, Lissy, 51, and Clea, 47.

Newman and his first wife Jackie Witte had daughters Susan, 59, and Stephanie, 58. Their son Scott died of a drug over­dose in 1978 at age 28.

In his will, the star of “The Sting” left the remainder of his assets, including his personal property and real estate, to Joanne.

He specified that his Os­car statuette for “The Color of Money” was to go to his Newman’s Own Founda­tion, and that his aircraft and race cars be sold, with the profits going to a trust he created. Together, he and Joanne ear­marked the majority of what was left for the foundation and other charities.

But with their mother’s mental state deteriorating, sources say the Newman girls are hoping to challenge the will. However, a legal expert believes they’d face an uphill legal battle.

“As for Ms. Woodward’s declining health, if she’s unable to carry out her duties, (either) a co-executor can step in or a new executor is appointed,” Francis Harvey, a New York City trusts and es­tates attorney told The ENQUIRER.

Several of the daughters feel that clause “might give them some wiggle room, especially if they can sway an­other executor to divvy up less money to charity and more to the children,” said the source. “But the very idea of ques­tioning their father’s estate plan has Joanne’s three daughters not speaking to their half-sisters.

“Joanne recently moved in with Lissy, and now Lissy could become the villain. I think the other girls fear she might influence Joanne when it comes to dividing up the family jewelry, art and memen­toes.

“In my opinion, the bottom line is that the girls are being greedy – and it would break Paul’s heart to know a catfight is brewing over his money.”