Source: Johnston, Alexander, Jr., Genealogical account of the family of Johnston of that ilk, formerly of Caskieben, in the Shire of Aberdeen, and of its principal branches. Edinburgh, 1832.
Gilbert de Johnston - In his fathers lifetime designed of Ballindauch. He got, 10 November 1430, from his kinsman, Henry de Leighton, Bishop of Aberdeen, a lease, "Gilberto de Johnestoune, totam villam de Bischope Clyntre" for all of the days of his life, for payment of an yearly rent of one merk Scots. (These lands leased from the Bishop of Aberdeen to Gilbert were those known as Bishop's or Little Clinterty, in the parish of Saint Machar, now Newhills) He married first, Elizabeth Vaus or Vans, the daughter of the Laird of Menie, in Aberdeenshire "ane man of great neme and estimation for the tyme" by whom he had one son, his successor, Alexander, and three daughters whose names are not known, but of whom the eldest married the Laird of Birkenbog in Banffshire; the second married the Laird of Blackhall, and the youngest married William Hay of Artrachie. (Richard Waus or Vaus of Menie, Burgess of Aberdeenshire, granted to the Franciscan or Grey Friars of that city, anno 1469, the lands and property belonging to him, situated on the east side of the Broadgate for their monastery.) Gilbert married secondly, a daughter of Sir Alexander Forbes, second baron of Pitsligo, in the shire of Aberdeen, by his wife had a daughter of the family of Errol; and by that lady he had a son, William "who was provydit to the lands of Bandauch" This William got a crown charter "Gulielmo Johnstoun de terris de Ballindauch" dated 31st August 1472; and of him were descended the Johnstons of Crimmond. Upon the death of Gilbert, which took place previous to the year 1481) the succession opened to his eldest son.
[NOTE: There is some confusion about Gilbert. He may or may not be the father of Alexander. If he is not Alexander's father, Gilbert Junior, son of the above Gilbert, who married Elene Lichton is.