Seamus the car roof dog was claimed to have been given to given to Romney's sister who had a farm and that it live to a "ripe old age"
"Two of Romney's heirs, however, are reported to have casually contradicted this, off record, saying Seamus actually ran away once the family reached their destination.[8]"
I think I'll believe the 2nd version. Dogs are very smart.
wikipedia
Mitt Romney dog incident