Republican presidential candidate Rick Santorum says it's fair to criticize former Massachusetts Gov. Mitt Romney for putting his dog on top of his car because because it speaks to his character.

According to a 2007 Boston Globe profile of the Massachusetts Republican, Romney’s oldest son, Tagg, yelled, “Gross!” as he noticed a brown liquid flowing down the back window from the Irish Setter Seamus, who had been riding on the roof of the family's station wagon for hours.

“As the rest of the boys joined in the howls of disgust, Romney coolly pulled off the highway and into a service station,” the Globe noted. “There, he borrowed a hose, washed down Seamus and the car, then hopped back onto the highway. It was a tiny preview of a trait he would grow famous for in business: emotion-free crisis management.”

ABC News correspondent on Sunday asked Santorum if it was fair for his adviser, John Brabender, to slam Romney over the incident.

"As far as Seamus the dog, look, the issues of character are important in this election," Santorum replied. "And we need to take a look at all those issues and determine if that's the kind of person you want to be president of the United States."