The Gossip Girl star's children have a protector in Australian cattle dog Oliver

It seems Kelly Rutherford’s kids don’t need a bodyguard – or a nanny. Their dog, Oliver, thinks he’s both.

“He’s very bossy,” the Gossip Girl star told PEOPLE at a Kiehl’s store opening in New York on Tuesday. “He really shows boundaries with the kids.” PHOTOS: Stars’ Babies – and Furbabies!

Oliver, a 15-year-old Australian cattle dog, also shows his sweet side with Rutherford and her children, 4½-year-old son Hermès, and 2-year-old daughter Helena. “He’s a doll with them,” she said. “He loves them and protects them. They love him!”

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