And additional: If there were concerns about her ancestry, did these resurface when it became clear she'd be queen instead of just married to the spare.
? Elizabeth Bowes-Lyon was the daughter of Claude, the 14th Earl of Strathmore and Kinghorne (in the Scottish peerage), when she married Bertie.
(If I wanted to be a pedantic snot, I would also note that, in England, the only non-commoners are those who have a title in their own right, which is rare. A peer's wife, sons, and daughters are therefore almost always commoners, though they may have titled by courtesy.)