My wife always get so anxious when I leave sauce simmering on the stovetop during the day

Jesus, Mrs. Duck, did they not cook any sauce when you were growing up?! That's what my parents always did, just leave sauce simmering all day long. It lets all the ingredients get to know each other, as my dad would always say, making for some excellent quality sauce! And you know what? The house never burned down, as evidenced by my parents still living in it.