His ascent to power
By the 1540s Grey Colin was playing an active role in the Glenorchy lordship.
The third son
His eldest brother, Duncan, 4th laird (1523-36), had died without a male heir and been succeeded by his other brother, John, 5th laird (1536-50).
As John's health failed, Grey Colin took more responsibility and in 1548 he brought the Breadalbane troops to the 4th earl of Argyll's muster at Dunstaffnage Castle (GD112/39/1/1 & 2).
John died eighteen months later leaving three daughters but no male heir. After this series of dynastic failures, on 5 July 1550 Grey Colin became 6th laird in his late 40s.
Within six months of succeeding he made an advantageous marriage to Katherine Ruthven, by whom he had eight surviving children (see Kate).
For 33 years Grey Colin was laird, dying on 11 April 1583 and being buried at the Campbell chapel at Finlarig. His will was registered with the Edinburgh commissary court on 3 April 1584 (NAS CC8/8/13 fos. 133r-38r).