From the article, reporting an episode between Philip and Diana as told in "The Diana Chronicles":
The monarch's no-nonsense husband, who the recollections of today had for many years enjoyed a good relationship with Diana, told the increasingly independent Princess: "If you don’t behave yourself, my girl, we’ll take your title away from you."
Referring to her historic Spencer lineage, of which she was proud, the Princess called upon her famous quick wit, telling her father-in-law: "My title is much older than yours, Philip".
Ouch!
End of quote.
Ouch indeed! What a stupid and uneducated thing to say:
The duke of Edinburgh was born a prince of Greece and Denmark - a member of the oldest dynasty of Europe. His ancestors already reigned in Scandinavia when William the Conqueror had not been born. I doubt the Spencers are left-over Anglo-Saxon nobility thus Diana was simply wrong. IMHO in that case it is not quick witted or even funny, but an uneducated kind of pertiness.
