Roberto's widow has died at 78 years old. MLB has a nice piece about her at:
https://www.mlb.com/pirates/news/vera-clemente-passes-away
In Maraniss' biography of the Great One he relates a story about how Roberto went to visit Vera's father to ask if he could marry her. Her dad was reluctant, thinking that as a ball player Clemente just wanted a pretty woman and wouldn't be much of a husband. Roberto convinced him by saying something like "As a ball player I can have any girl I want, but I don't want just any girl. I want Vera." It seems he chose well.