Daughter of Walter Cary, granddaughter of Trumball Cary, friend of William Seward. Mentioned by her grandmother Margaret Cary in a March 10, 1856 letter to Frances Seward, "Walters health although not worse than for years past is still a cause of constant anxiety for our old age- and his little family with their aches and pains and waywardness a great care." Walter Sr. took his wife and oldest son to Cuba that year, leaving little Jennie and two of her siblings with their grandparents.