Hello little one! Jointure is kind of like a promise between two grown-ups who are getting married.
You know how when mommy and daddy got married, they promised to love and take care of each other forever? Well, jointure is a special promise that often comes with getting married.
It means that if one person in the marriage passes away, the other person will still be taken care of. They will get some of the things that the person who passed away had, like money or property.
It's like a backup plan to make sure that nobody is left alone and sad if something bad happens. So, it's important for grown-ups to talk about jointure and make sure they agree on what will happen if one of them isn't around anymore.