only another yorkie mom/dad understands -- i have 4 and foster thru Save a Yorkie Rescue.  my family says the same thing - "are you crazy?"  i just tell them they are like lays potato chips - you can't have just one!
 
i just know that one of these days i will fail "fostering 101" and end up adopting another pup.  at this point, what's one more!