Fred M could be F. B. Macdonald, brother of Charles. Frederick was wounded by shrapnel in June 1915 at the same battle in which Charles was taken prisoner.

Photo is one of a collection saved by Corporal Charles  Henry Lawrence Macdonald of the 15th Battalion who was a POW after the battle at 2nd Ypres in April 1915.

The photo is of the Senior NCOs of No. 2 Company, 15th Battalion (48th Highlanders) and was taken in August 1917 at Noeux-les-Mines, France just prior to the battle of Hill 70. The battalion mascot Bruno is visible in the image.