Jack Nicholson was born on April 22, 1937, in Neptune City, New Jersey. He grew up in a modest household, and his early life was marked by challenges. His mother, June Nicholson, was a showgirl, and Jack was raised by her and his grandparents. He didn’t find out until later in life that his mother was actually his older sister. The revelation came when he was in his late 30s, adding an emotional layer to his already complicated childhood.