Here's a nice article on Jeannie Schulz, widow of Charles, who now manages his legacy and a very lovely museum up in Santa Rosa.
My pal Sergio and I went there a few years ago and got the grand tour, including Jeannie taking us across the street and showing us the skating rink, which I loved. I also liked the fact that in the Schulz Museum, there are Peanuts strips printed on the tiles that ring the men's room. You're not supposed to take photos inside the building but I was alone in there.
Mainly though, I enjoyed meeting Jeannie. Charlie Brown, Lucy, Linus and all the rest couldn't be in better hands.