A famous bassist and longtime friend of pop megastar Prince says the artist found "real happiness" in his faith and could stay up all night talking about the Bible.

Larry Graham is best known for playing in the funk band Sly and the Family Stone and with his own group, Graham Central Station. He also toured with Prince. Graham tells The Associated Press that Prince became a Jehovah's Witness later in life and that it changed the star's music and lifestyle.

Prince was found dead in his suburban Minneapolis last month. Investigators have not released a cause of death.

Graham says while Prince knew it was important that his music brought people happiness, his "biggest joy" was sharing scripture with people.