Why do Michael Jackson's children appear to be so white/caucasian?

I have seen this question a few times before and to rebuke many answers I have taken university level genetics classes and read a few books in dealing with genetics. Calling me racist is kinda a shibboleth here, I am just wondering if someone could confirm my inclinations that they are adoptive children. People who ask why do I care; why care about anything, why is the sky blue. I saw the pictures of Mr. Jackson's children and wondered what circumstances produced these children who appear to be caucasian. The controversy about his skin color alone should allow the question in a "post racial" society. I am pretty sure they are adopted children, but thought I'd ask the internets.