Dedications to an individual by members of his immediate family were common throughout the Greek world, but in Rhodian territory a more complex form of family dedication is attested, with several members of the wider family circle participating and listing their exact relationship to the honorand. When these inscriptions with their various kinship terms are correctly interpreted, stemmas of large family groups may be drawn up. The method which must be used in understanding these ‘family monuments’ is shown by an analysis of IG xii (1) 72 a–b, and the texts of four similar inscriptions are examined and revised so that family trees may be created for their family groups (ILind 382 b; Inschr. Nisyros 3 with IG xii (3) 103; IG xii (1) 107, the most complex of all Rhodian ‘family monuments’). The presence in IG xii (1) 107 of Hagesandros the son of Paionios, one of the three Rhodian sculptors of the Sperlonga and Laocoon statuary groups, leads to a reconsideration of the date of the groups and of the career of the only one of the three sculptors otherwise attested as an artist, Athanodoros the son of Hagesandros. It can be shown by securely dated pieces of epigraphical evidence that Hagesandros and Athanodoros were born c.80 BC and had their artistic floruit early in the reign of Augustus. The Sperlonga and Laocoon sculpture must therefore be dated to this period.