I am very sorry for the loss of your sisters precious little yorkie. iMO, the best way to handle it is to call your sister and tell her , even though she is on vacation. It is important not to wait becaust this was a tragedy. It is going to be even more difficult to wait until she comes back to let her know then to tell her right away. If something happened to my Suzi while i was gone, I would want to know . I would even be more devastated finding out later then as soon as it happened. This was a horrible accident.
Be prepared though , your sister may either be in shock, start to scream , swear, cry, or panic. Let her do what she needs to do to let her grief out. This is going to be a extremely hard , and emotional time for her.
