Adam appears to have enjoyed the favour of the Scottish king Alexander III, and married Marjory daughter and heiress of Neil, Earl of Carrick. He was able to use the title of earl in his wife's name, but it is unlikely that he had much role ruling the province, as Earl Neil had left the position of kindred chief (ceann cineil) to his nephew Lachlan. Although they had no son to take over the earldom for the Kilconquhar family (that went to the Bruces), their daughter was the mother of Robert Bruce's companion in arms Thomas Randolph, Earl of Moray.
He died at Acre in 1271, while on crusade.