Hi!
I think it hasn't come up earlier, but after reading Alison Weir's biography on Henry VIII, i've discovered that the Lady Margaret was a very flirtatious (how euphemistic) young woman. She was imprisoned in Syon House in 1540 because she became involved with Catherine Howard's brother Charles. She was imprisoned there and Charles was sent to Calais, where he died in late 1542. Margaret would only be released from Syon House in November 1541, when the building was to be used as a prison for a more important person...