Thomas A. Twomey’s sudden death in November came just five months after the grand-opening ceremony commemorating the East Hampton Library’s $6.5 million expansion and renovation. Mr. Twomey, a lawyer, civic leader, and chairman of the library’s board of managers, had played an integral part in the yearslong project, which added 6,800 square feet and houses the new children’s reading room and the Baldwin Family Lecture Room.