[5] Katherine Manners was selected by the formidably ambitious Mary Villiers, Countess of Buckingham, to marry her son.

Invited to visit the Countess of Buckingham, Katherine was forced to spend the night due to an attack of illness.

Believing his daughter's honour to be compromised, the Earl of Rutland refused to receive her back, and demanded that George Villiers marry her immediately.

[8] The Duchess of Buckingham was one of the few women of rank of the time whose "gentleness and womanly tenderness, devotion and purity of life", were conspicuous in the midst of the "almost universal corruption and immorality of the Court".

No scandal was ever breathed against her name, and the worst that was ever said of her was that by her influence she at one time nearly persuaded her husband to become a Roman Catholic, she herself having returned to her own faith soon after her marriage.

A surviving pair of chairs carved in an Italian style, and painted with Villiers and Manners heraldry, may have been used in a gallery.

Upon the death of her father in 1632, without male heirs, she succeeded suo jure to the ancient barony of de Ros.

[19] Following the Catholic uprising in Ulster in 1641 the MacDonnell family moved south to Wexford, then Waterford, where Katherine died in 1649.