Here's a two-row bar to a career US Marine in my collection who fought in WWII and Korea. Both Purple Hearts were earned in Korea
And here's a two-row (displayed as a single long row) to a WWII and Korea War veteran. He served as an enlistedman in Iceland with the Marine Corps and fought in the Battle of Guadalcanal, where he was wounded severely enough to be stuck stateside for the rest of the war. A few years after the war ended he joined the Army as a Warrant Officer and served in Korea with them. Interestingly, it seems that aside from his ribbons and a few photos, that he didn't keep anything from his time in the Army, but did keep a lot from his Marine days. I also have his Marine Corps ID, some EGAs, and his polar bear patches from Iceland