William married Katherine Elizabeth Cunningham, Countess of Lochinvar in 1579 in Helington, Elderslie, Renfrewshire, Scotland. Katherine (daughter of William Cunningham, 6th Earl of Glencairn and Janet Gordon of Lochinvar) was born in 1555 in Elderslie, Ayrshire, Scotland; died on 6 Apr 1611 in Elderslie, Renfrewshire, Scotland. [Group Sheet] [Family Chart]