From Slate dot com:
It's hard to imagine a modern family as prominent in as many ways as Philip Sidney and his sister, Mary Sidney Herbert, Countess of Pembroke were. In addition to the social and political prominence of the Kennedys and the wealth of the Kochs, beyond their personal glamour and estates and Philip Sidney's heroism in war, the brother and sister were at the center of scholarship and art—two realms that were less separated in their time than in the present.
Mary Sidney, proficient in Latin and ancient Greek as well as modern European languages, was a brilliant translator as well as a writer in prose and verse. Active as a patron of the arts and a host to artists, she was the center of a circle that included, in addition to her brother, poets Michael Drayton, Edward Dyer, Fulke Greville, and Edmund Spenser.
Her translations of the Psalms (continuing a project of her brother's, after his death) are said to have influenced, in a following generation, her cousin once removed George Herbert and John Donne.