After your grandfather fought to take Italy, and make it a reasonably safe place for the Allies, my own father was stationed at Foggia, Italy. The US based the 15th Air Force there, to bolster and supplement the 8th Air Force, which had already been flying from bases in England.
Unlike in England, the bomber guys were encouraged not to fraternize with the Italian civilians. Lord knows, those poor souls had been thru hell, life under Mussolini, then basically occupation by the Nazis. Dad's friends had one guy that spoke Italian, and bartered with the natives for fresh eggs. Other than combat, I think Dad's most hated experience was the powdered eggs. Heh!
Like your grandfather, and the entire generation of WWII vets, Dad didn't speak of his experiences for years, until his three sons were grown, and continued to ask about it. I think it was a catharsis when he finally started relaying some of his experiences. He witnessed Forts next to his own shot down in flames by the flak anti-aircraft fire.