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"And he would come with no security and nannies," Cascio said. "That's when he was himself."
Cascio said Jackson paid his family such a visit earlier this year and got a lot of joy from the pleasures of a simpler life.
"He would even help my mom vacuum the rug," he said. "He would, like, help clean up the house. And he was just a real human being."
Cascio said the two would even sneak off to hit the local stores or have dinner unnoticed.
"Sometimes we would sneak out ... with no security," he said. "And I would get him all dressed up in disguises."
"You know," Cascio continued, "everyone can walk down the street and go shopping. And, you know, we take that for granted, but he could never do that."
Cascio also praised Jackson as "the perfect father."
"He was the greatest father in the world to those kids," he said.
Cascio also remarked on Jackson's close relationship with his mother, Katherine Jackson, who now has custody of Prince Michael I, 12; Paris-Michael Katherine, 11; and Prince Michael II, 7, known as Blanket.
Cascio said he believes his good friend would be "very humbled" by the outpouring of grief and love from his fans.
Cascio met Jackson when he was 5 years old, and the two maintained a steadfast friendship that outlasted the highs and the lows. He worked as Jackson's personal assistant and traveled with the icon all over the world.
An Enduring Friendship With Michael Jackson
During what may have been the lowest point in Jackson's life, Cascio was by his side, although as a co-conspirator Cascio was accused in 2003 of helping Jackson muzzle a boy who claimed the entertainer had molested him. Cascio was never indicted and has denied ever seeing anything inappropriate during the considerable time he spent at Jackson's Neverland Ranch.
In 1993, New York City newspapers and The Associated Press reported that Cascio was one of two boys that a housekeeper allegedly saw naked with Jackson.
But 12 years later, in 2005, Cascio told ABC News' Cynthia McFadden that, as boys, he and his brother slept in Jackson's bed while the singer slept on the floor.
Cascio said that he and Jackson, along with the accuser and the accuser's brother, slept together in the same bedroom at Neverland.
"It's like having a sleepover with a bunch of friends all in one room, watching movies, doing this," Cascio told McFadden.
But today, as the world says goodbye to Jackson, Cascio said it was not the time to talk about that time in their friendship.
"I think today is just -- focus on what a wonderful human being he is," he said, "and not talk about the past."
ABC News' Russell Goldman contributed to this story.