My grandfather served in WWI as a Marine. All but one of my great-uncles (one had flat feet and didn't qualify to enlist) also served during WWI in either the Navy or Marines.
My uncle Robert was also a WWII vet- he was Army- and received a battlefield commision to LT during the Battle of the Bulge. (He died in '97.)
There's been at least one member of every generation in my family as far back as can be traced- about 30 generations. Must be in the blood!