(Estar) careca de saber - (To be) bald from knowing
The Brazilian equivalent of “to know full well”
ie. Você está careca de saber que eu sou alérgica a gatos - You know full well that I’m allergic to cats
A variant of this is saber muito bem (to know very well).
…You know, the more I translate these the more I realize how weird languages are. Most of the time we’re really just babbling nonsense that for some reason we think sounds logical.