He was succeeded by his brother Robert, a man of note in the affairs of the county. He confirmed the charter of Burscough and added the land of Adam de Birkes, which his brother Richard had bequeathed with his body, as well as two other plats. By his marriage with Joan, sister and coheir of Thomas son of Robert de Alfreton, he became possessed of a moiety of her father's estates in Alfreton, Norton, and Marnham, held of the honour of Tickhill. She probably died without issue, as these manors did not remain with the Lathom family. Robert was made a knight in 1243 in consequence of the king's writ to enforce knighthood on all who had an estate of fifteen liberties of land. In 1249 the county and castle of Lancaster were committed to Sir Robert, during the king's pleasure. By this appointment he held the office of sheriff from Easter, 1249, to Michaelmas, 1254; he held it again from Easter, 1264, to Michaelmas, 1265. His second wife was Joan, daughter of Adam de Millom, by whom he had several children. From 1277 until his death about 1290, he was engaged in wars.
