Pippa Middleton and James Matthews’ future titles of Laird and Lady of Glen Affric are honorary titles that came with the purchase of a large amount of land. As such, they carry a different weight and aren’t hereditary, which is why their children wouldn’t take on the titles. “[Matthews’] father bought a feudal barony,” royal historian Marlene Koenig told Town & Country in 2018. “‘Laird’ is not a title, but a description applied by those living on and around the estate.”
British journalist Duncan Larcombe further explained that ownership of land in itself isn’t enough to earn anyone any actual titles. “James is heir to a fair amount of land, but it is nothing like a proper title,” he said. Feudal baronies are different from peerages, which in England come with the nobility titles of duke, marquess, earl, viscount, or baron — depending on the rank. Peerages are inherited, though they can also be granted by a sovereign. Thus, Prince William could technically bestow a title on Pippa when he ascends to the throne.
That’s unlikely, though. A more likely scenario would be for a future King William to grant titles to Carole and Michael Middleton to end their run as Britain’s first and only grandparents of a future king to not have one, The Telegraph noted. In that case, Pippa would become a Lady, but her children would still not have any titles because her little brother, James Middleton, would be the one to inherit the peerage.