Lawrence and Helen had six sons and two daughters:
Hugh, succeeded his father
Catherine, married David Fairlie, of that Ilk
Isabel, married Gavin Blair of Hally
Thomas, of Jordanhill
In 1547, Lawrence exchanged the lands of Crawfordjohn for the lands of Drumry, with James Hamilton of Fynart. He died within the year, at Kilbirnie.
Crawford, Fred E., "The early ancestors of the Crawfords in America : an introduction to genealogies of American families of the name", (Cambridge, Massachusetts,,1940)
O'Hart, John, "The Irish landed gentry when Cromwell came to Ireland", (Dublin: J. Duffy, 1887)
Paul, James Balfour. "The Scots peerage : founded on Wood's ed. of Sir Robert Douglas's Peerage of Scotland; containing an historical and genealogical account of the nobility of that kingdom" (Edinburgh,David Douglas,,1908 Vol. V
Robertson, George, "A Genealogical Account of the Principal Families in Ayrshire, More Particulary in Cunninghame", (Irvine, Cunninghame Press, 1823)
It may be possible to confirm family relationships with Lawrence by comparing test results with other carriers of his Y-chromosome or his mother's mitochondrial DNA.
Y-chromosome DNA test-takers in his direct paternal line on WikiTree:
Wayne Prather :
Family Tree DNA Y-DNA Test 111 markers, haplogroup R1a1a-CTS4179, FTDNA kit #78145 +
Y-Chromosome Test 111 markers, haplogroup R1a1a