A Family for Felix — Kathryn Kirkwood

Every afternoon, the cat that belongs to Lord Stonehill's sister disappears, only to return with a new toy or a bright ribbon. Intrigued, Stonehill follows the feline Felix, and finds the puss has a young family--and a new friend, the lovely Miss Margaret Whitmore, an avowed bluestocking. Stonehill thought London held no new pleasures...until Felix introduced the jaded peer to this special young lady.