What killed Henry eighth son?

Henry VIII and Jane Seymour's son, Edward, was Henry's only legitimate son. Edward became King Edward VI in 1547 at the age of 9. He died in 1553 at the age of 15. Probably from tuberculosis. There is no evidence, at least that I am aware of, that he died anything other than a natural death. Henry had at least one illegitimate son, Henry Fitzroy, later Duke of Richmond. He was, if I remember correctly, the son of Henry and Bessie Blount. Fitzroy died in 1536 and it was suspected that he died by poison - perhaps Anne Boleyn and her brother George, Lord Rochford had something to do with it, and perhaps they didn't.