When you hit a brick wall, consider hiring a pro. The Society of Genealogists and the Institute of Heraldic and Genealogical Studies have accredited experts who specialize in noble lineages. They can access archives you can’t—like Vatican records or closed royal account books.
Expect to pay hourly rates, but the payoff can be thrilling. One client discovered they were a direct descendant of Edward III through a forgotten marriage of a younger son. Pro genealogists also know that royal blood often flows through illegitimate lines, which aren’t always recorded in official peerages.