The woman he had called Mom had been his grandmother, but she had also been the person who built the household in which he grew up. Those are not contradictory facts. The woman he had called sis had been his biological mother, but she had also been the person he had mourned as a sister in 1963. Those are not contradictory feelings, even though they belong to different relational categories.
Jack Nicholson came from Neptune City, New Jersey, from a working household on the shore, from a woman who ran a beauty salon and painted oils and kept a secret for thirty-seven years without cracking. He came from a biological mother who called herself his sister and died of cancer at forty-four having never told him the truth. He came from a biological father whose identity is, to this day, uncertain in the public record, and which he has chosen not to pursue with the technological certainty that would have been available to him for decades.
He also came from a decade of B-movies and persistence, from a last-minute casting decision that turned into an Oscar nomination, from five decades of films that made him one of the most studied and celebrated American performers of the twentieth century.
None of those origins cancel each other out. They are all part of the same person, the same life, the same thirty-seven years of formation that preceded the phone call from Time magazine.
The phone call changed the label on two relationships. It did not change the relationships themselves, because those had already been fully lived. The name he had for what Ethel May and June had been to him was wrong. What they had actually been to him — the people who were present, who raised him, who helped form the person he became — that was not wrong at all.