The first wife of Pietro Viani, Brigida died after having two children (Pietro and Geovanni Batistta) and her sister Pasqualina married Pietro. They then had the other children.

This, of course, doesn't make any sense since she allegdly died in 1909 and Brigida's sister, Pasqualina, is reported to have died in 1906, three years BEFORE her sister?

Pascualina is also reported to have had five children, whereas only three make sense with the third named Terzo.