Lord Thomas Howard (1511-1537), son of the 2nd Duke of Norfolk Thomas Howard by Agnes Tilney, apparently by some sources had an affair with Margaret Douglas, niece of Henry VIII and daughter of his sister Margaret.
Due to this they were both sent to the Tower and Thomas died there. However, Margeret was released to Scion House in London. Was she pregnet with Thomas's child (Robert) as supposedly there was a Robert Howard born at the Scion house in 1537?
I cannot find any substantial historic reference to this. Various on-line trees have it but their source seems to be other people's trees.
The archives of the Dukes of Norfolk in England would not confirm it so I don't know the original source of this birth (myth?).
There was a succesion problem which caused their imprisonment as Henry had just bastardized his 2 daughters after his marriage to Jane.