Callum is the current captain of Scotland under-18 team, taking charge of the team for the first time in their game against England, in Newcastle, in March 2015.
Prior to skippering the side, he had made four appearances for the age-grade side.
The lock, who currently studies Rugby Performance at Edinburgh College, has captained Edinburgh at under-17 and under-18 level, as well as appearing for Edinburgh Rugby A against their Glasgow Warriors counterparts and Ontario Blues.
During his time at Stewart’s Melville College, he won the Brewin Dolphin Shield competition.