A technical question for a heraldic project

Not sure if this is a proper blog entry...


None of my books answer me to this case: If a family who incresed its coa has a quartered coat of arms with every quarter showing another single coa, original shield is on the top right, and then the first son marries a woman who inherits her families coa so it is added, what happenes to their son's shield: Is the new part added and the original family shield becomes a heart shield? Is it somehow quadrupled? I am totally stunned noone seems to know. 0o

Thanks for the help!