In 1301, Pope Boniface VIII issued the papal bull authorizing the marriage, but since both were underage, it was postponed until 1309 when Afonso was eighteen years old and Beatrice had turned sixteen.
În 1301, Papa Bonifaciu al VIII-lea a autorizat căsătoria, dar cum mirii erau încă minori, nunta a fost amânată până în 1309 când Afonso avea 18 ani iar Beatrice 16.