His collateral relative, Gillis van Aertrycke, was burgomaster of Bruges in 1300-1301, 1334-1335, and 1336-1337. Gillis was the first of his family to hold the lordship of Tillegem. Furthermore, Josse's ancestor, Simon (1320 - 1368), held the same office between 1348-1349, 1361-1362, and 1362-1363; and so did his paternal cousin, Philippe IV (1420 - 1470), in 1469-1470.
