From The Letters of J.R.R. Tolkien
An account dealing with, of all things, hobbit family politics...

The household was not a 'monarchy' (except by accident). It was a 'dyarchy', in which master and mistress has equal status, if different functions. Either was held to be the proper representative of the other in th case of absence (including death.) There were no 'dowagers'. If the master died first, his place was taken by his wife, and this included (if he had held that position) the titular headship of a large family or clan. This title did not descent to the son, or other heir, while she lived, unless she voluntarily resigned....It could, therefore, happen in various circumstances that a long-lived woman of forceful character remained 'head of the family' until she had full-grown grandchildren.

A well-known case, also, was that of Lalia the Great ( or less courteously the Fat. ) Fortinbrad II, one time head of the Tooks and Thain, married Lalia of the Clayhangers in 1314, when he was 36 and she was 31. He died in 1380 at the age of 102, but she long outlived him, coming to an unfortunate end at the age of 119. She was not at the famous Party, (SY (ed. Shire Year) 1401), but was prevented from attending rather by her great size and immobility than by her age. Her son, Ferumbras, had no wife, being unable ( it was alleged) to find anyone willing to occupy apartments in the Great Smials under the rule of Lalia. Lalia, in her last and fattest years, had the custom of being wheeled to the Great Door, to take the air on a fine morning. in the spring of SY 1402 her clumsy attendant let the heavy chair run over the threshhold and tipped Lalia down the flight of steps and into the garden. So ended a life and reign that might well have rivalled that of the Great Took.
It was widely rumoured that the attendant was Pearl (Pippin's sister), though the Tooks tried to keep the matter within the family. At the celebration of Ferumbras' accession the displeasure and regret of the family was formally expressed by the exclusion of Pearl from the ceremony and feast;but it did not escape notice that later (after a decent interval) she appeared in a splendid necklace of her name-jewels, that had long lain in the hoard of the Thains.....

Hmmm... it seems that the Tooks, at least, had a more Machiavellian streak than one would have thought !