I've got a counting dog. For much of her life there were 4 people living in the house. Intermittently through the day she would walk around the house until she counted 4 people, then settle down. It didn't really matter which 4 people it was, just that there were 4, if there were more people in the house she'd stop at 4. As children moved away she'd have bad periods where she couldn't make quota and would keep searching. Eventually she'd update the target house population and only count to 3 or now 2.
My sister's dog is the same way with counting people in the house. She's a rescue, so we aren't sure exactly what her lineage is, but she has a color pattern somewhat reminiscent of a border collie, and she tries to herd people.
That's so cute!
Is it a herding breed?
This cat retreated to her lair after she got all plates, whether there 2, 3 or 4 persons at the table.
Other cats in the household developed the same pattern ( showing up, cleaning plates ). But these cats had to signaled explicitly there was none left, otherwise they would stay around and keep asking.