"And now, something terribly sad - apparently, his two oldest children aren't his. They were from a sperm donor, and their mother - MJ's wife after Elvis' daughter - doesn't want them in her life."
Just a correction with that, QueenSusan, Lisa Marie is not the mother of any of Jackson's children. Their mother is Debbie Rowe, whose parental status with the children is unknown. She originally signed away her legal rights upon their births, but then later successfully filed a suit to regain her parental rights.
As for their biology, while I do wonder whether they were actually his as they don't look biracial, they are still Michael's. He was their father. Their DNA won't lessen their grief at losing their father. By the way, is the question of their paternity actual or just gossip?
justBob