culture
门楣 is the lintel above a doorway. Historically a wealthy or distinguished household would carve plaques into it announcing official titles or honors, so 'lighting up the lintel' literally meant adding a new plaque. The idiom evokes a very physical image of family achievement.
register
Formal and literary, used positively about achievements that reflect well on parents and ancestors: passing the imperial exams historically, top university acceptance or career success today. Often heard at weddings and graduations.
