At age 37, actor Jack Nicholson discovered that the woman he'd always known as his sister was actually his mother.

Nicholson had been born the illegitimate child of 17-year-old June Nicholson. Because of the close proximity in ages, Jack had always assumed that June (his mother) was his sister. Similarly, he had always been allowed to believe that his grandmother, Ethel May (June's mom), was HIS mother.

Even on their deathbeds, neither June nor Ethel May had revealed the truth to Jack!

Nicholson finally discovered his true lineage in 1974. A reporter for Time magazine had unearthed the truth and called Jack to verify his findings.
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