My grandfather from the father's side served in HMG squadron 1st Uhlan Regiment in September 1939 and his cousin served as AT rifle gunner in this regiment.
On 11th september - during one of the most tragic events of september campaign (battle between two polish units - uhlan regiment and infantry battalion when many good people died - including 1st Uhlan Regiment commander) my grandfather's horse was killed, and he lost his boot under the horse's body. Separated from his unit, he decided to return home, but about week later was arrested by Russians. He was lucky - because he was simple soldier, so they let him free few hours later.
During the ocupation he served in Homeland Army - probably as a engineer platoon comander (but we are not sure ). In june 1944 almost every male from grandfather's family were executed by Germans during village pacification - but grandfather again managed to escape. After the war - he was again arrested by Russians and spend some time in coal mine.He died in 1987.
My grandfather from mothers side was too young to fight in WWII, but was almost executed by Germans, when they find Jewish hideout in his village. To this day he don't understand why they let him, and his family free.
My grandmother spend four years on german farm as a "slave'.
He also was very lucky, because they treated her very well (As she said it was realy rare). Maybe because of fact, that she was very young, and they lost their only son in 1941 on eastern front.