Encourage your parents (and other close friends/relatives) to WRITE YOU -- the old snail mail -- as often as possible during the summer and then I suppose move to email once Ac Year starts.
In the "old days" of newspapers, my mother sent me clippings from the local papers. My father wrote a short letter EVERY SINGLE DAY. Just nonsense stuff like what the dog had done, what the neighbors were doing, what he and my mother were doing, etc. And he passed along advice that he'd learned as a WWII Marine in the Pacific theater -- little pearls of wisdom that helped keep me going.
Looking back now, I realize just how special those letters were and how I looked forward to mail call b/c I knew I'd have a letter from him. Even at the time, all of my classmates were "jealous" that I got mail every single day. Jealous in a good way -- it's hard to rag on someone when their dad is writing them a letter. Those letters were priceless and I only wish I'd saved them.
You don't have to be an author. You don't have to have exciting tales to tell. And your plebe WILL have time to read the 3-4 paragraphs you manage to jot down. Just being reminded that the life they've left is still ongoing is such a wonderful thing. And you as a parent/relative, etc. definitely have more time than your plebe.
So, from Day 1, pick up your pen.
BTW, one little trick my dad learned -- number or date your letters so that if more than one arrives on the same day, your plebe can read them in order.