A couple of years ago my uncle told me about my maternal grandfather's (who died of cancer before I was born-) service during the Winter war and Continuation war & I filled some of the blanks based on his "Soldier's Passport", a passport-like document recording his military service, here's what I know so far:

My grandfather did his mandatory military service in Pori Regiment in 1938-39 and mustered out in April 1939, he reported in to "An Extra Refresher Exercise" (which was actually a cover story for a mobilization-) on October 12th 1939, he and the rest of his activated unit were taken to Hämeenlinna to await a train to take them to the border, while his unit was waiting for the train my grandfather decided to go AWOL to get a drink or a dozen & by the time he woke up the next day his unit had already left, he presented himself to Army officials who chewed him out before issuing him orders to report to Light Detachment number 13 & that's where he spent the Winter war driving horse-drawn wagons until he was relieved from duty in May 1940.

He reported for another "Extra Refresher Exercise" on June 17 1941 and was assigned to the regiment HQ as a horse messenger in Infantry Regiment 23 and went to the Svir front along with his regiment, in the spring 1942 he was reassigned to Infantry Regiment 44 as a horse wagon driver once again, in August 1943 he went AWOL from his unit on the Svir front (my uncle says he went on another binge in a similar fashion to what he did in 1939-) and was punished for it, he was relieved from duty for one last time in his home town in November 1944, he spent the rest of his life working as a lumberjack in his hometown & playing various instruments such as mandolin, balalaika and harmonica in his spare time, it appears he hated both war and guns for the entirety of his post-war life and none of his children have ever owned firearms, but all of them love music and most of them play at least one instrument.

All in all he was a prime example of a Finn from Häme (the province he was from); a quiet and unassuming man & a hard worker who was a heavy drinker yet always did his job (his military shenanigans notwithstanding.)

RIP Heikki.