Who called from 2012040704

This person has been calling me at least twice everyday, and it's getting extremely frustrating. It's been going on for months now.

MY MOM CALLED ME IN CT FROM HOME AND INSTEAD OF HER NUMBER COMING UP ON MY CALLER ID, THIS NUMBER DID...THEN WHILE WE WERE TALKING A WOMAN'S VOICE CUT IN AND SAID TO HANG UP FOR AN EMERGENCY CALL .....WHY DID THIS NUMBER COME UP AS MY MOM'S NUMBER INSTEAD OF HER NUMBER????   WHO DOES THIS NUMBER BELONG TO???