XV. John Dennistoun succeeded his father, and in 1725 got a charter of novodamus of his lands of Colgrain, two Camis-Eskans, and Kirkmichael-Stirling. During his life the estate was entirely cleared of debt, and he was enabled to leave it to his son considerably augmented in value. To effect this, the most prudent management was indispensable, and Colgrain seems to have abstained from taking any part in the public events which convulsed Scotland during his time, in order to devote his whole attention to his private affairs. That his feelings were in favour of the Jacobite cause, we have evidence besides the family tradition, in his uniform absence from all meetings of the gentlemen of his county about 1715, as most of these were noted for their attachment to the Hanoverian succession. He married, in 1700, Jean, only child of Moses Buchanan of Cummings-glen, a younger son of Carbeth, by Jean, eldest daughter and co-heiress of William Hamilton of Auchentoshan. Through her he succeeded to certain claims upon the estates of Glinns (or Cummingsglen) and Branshogle, in the county of Stirling, which he submitted to arbitration in 1708, and obtained decreet for 4,747 merks, 5 shillings, and 4 pence Scots. They had seven sons and nine daughters, of whom only the following attained
a mature age
1. James.
1. Margaret, born 1701, died unmarried, 1793.
2. Jean, married, in 1735, to John Brown, afterwards Provost of Glasgow
3. Janet, married, in 1733, to John Stevenson, merchant in Glasgow, and died without issue, aged eighty-two.
4. Grizel, married, in 1735, to William Dunlop, shipowner in Glasgow, and had one son, who predeceased her.
5. Elizabeth, married, 1752, Patrick Carnegie, shipmaster in Port-Glasgow, with issue.
