Up until recent more times a 16 year old male was considered a man, often started a family and was expected to make his way in the world. I’d be surprised if there weren’t 16 year old soldiers in the CW. There were such in WW1 and WW2 as well.
Not many 16 year old males (or even females) married, some, but the kid marriage image is largely a myth.
A lot of us dug pretty deep into average marrying age back during the Mitt Romney period and a lot of Mormons were selling the 15 year olds marrying as the normal thing in the past.
My own grandmother was 15 when she married my grandfather who rode a horse into her church to impress her, he later became a Deacon after settling down, but 15 was way younger than the average.