Donald was brother to Angus MacKay, Queen Victoria's first piper. He was an accomplished piper and was awarded many prizes throughout the 1820's and in 1834 became piper to His Royal Highness the Duke of Sussex and Earl of Inverness. He made the Prize Pipe for the Northern Meeting competitions from 1842 to 1845.

Angus MacKay was appointed piper to Queen Victoria on July 25, 1843. The bagpipes pictures herein are nearly identical and bear silver that was tested and  hallmarked in London in 1843. It is very plausible that Donald made this bagpipe as a gift to his brother to commemorate his new position. Angus suffered mental illness and his tenure came to an end in 1854. He was awarded a royal pension and was institutionalized in Crichton Royal Hospital in Dumfries. He was 43 years old. Three years later he escaped and drowned in the River Nith.
Angus MacKay
Angus MacKay
The bagpipe below was spotted on a Facebook page and was said to be a MacDougall. Something struck a chord with me and I quickly contacted the owner and asked for better pictures. The "reward" was that we were able to confirm, through the hallmarks, that the silver was tested in the London Assay Office in 1843. The rest of the bagpipe lined up beautifully with the Angus MacKay pictured above. I'm very happy and confident that we have correctly identified this instrument.
Donald MacKay - London 1840  1850