My cat is able to differentiate between people traversing the stairs to my front door (purely by the sound). The pacing and weight is usually very unique from o

My cat is able to differentiate between people traversing the stairs to my front door (purely by the sound). The pacing and weight is usually very unique from one person to the next. She will consistently jump up from my lap to greet a beloved family member at the door, but never gets up for guests.