Great emancipator portrayer DANIEL DAY-LEWIS’ bitter feud with his own brother after “enemy collaboration” on tell-all shocker.

“LINCOLN” star Daniel Day-Lewis is the toast of TinselTown after winning his third Best Actor Oscar for his portrayal of the 16th president – but there is one family member who may never get a chance to congratulate him.

Daniel hasn’t spoken to his half-brother Sean in 19 years! The rift is the result of a bitter fight that erupted when Sean, 81, helped an author with an unauthorized biography of Daniel.

NOW, Sean, a ex-journalist, desperately wants to get back in touch with the 55-year-old super­star, and he insists the only help he gave the author of the unauthor­ized biography of Daniel was a copy of his own earlier book about their famous dad, the acclaimed poet Cecil Day-Lewis.

“I wanted him to get the facts right, and he didn’t even do that,” Sean complained to an interview­er. “He got birthdays on the wrong days. It was full of errors. Anyway, he acknowledged my help in the foreword, and Dan saw that and completely blew me out of the wa­ter.”

Furious, the star of “There Will Be Blood” phoned his brother and told him to “****ing get a life” and to “**** off,” recalled Sean.

“I couldn’t get a word in. That was in 1994, and it was our last conversation.”

Ironically, Sean, who is Cecil’s son by first wife Mary King, was close to his half-brother when Daniel was growing up.

“We got on quite well,” he said. “I was allowed to beat him at ping-pong.”

They remained close when their father died of pancreatic cancer in 1972.

But the book Sean wrote about their dad, published in 1980, also upset family members because he decided to discuss his father’s extramarital affairs.

Now as he nears the end of his life, Sean still hopes to reconcile with his younger brother, who lives most of the time in Ireland.

But Daniel has turned a cold shoulder to his plea.