I bet your parents were pleased. They didn't have to do it themselves. Heh, heh. Yeah, they don't need much, if any training to herd. They just do it.
One of my GSDs when he was very, very young....still a pup really herded our little piglets when they escaped out of their place. He shouldered them all along this bank...all the way back to their fenced area where we opened the gate. He never had any training for that either.
Even my Doberman showed strong herding instincts and would herd his doggie playmates sometimes. My other dog, a mix would go chasing after a ball. Lyric couldn't care less about the ball but would block her like a cutting horse does with a cow. Dobermans have Rottweiler, (which is a herding breed actually) in their make up and also some old shepherds. So I guess Dobes sometimes have that tendency from those breeds. Or maybe it's simply play and lots of dogs do that a little bit anyhow. It is one of those things that all dogs have in them but it's just that some have it stronger than others.