AWW that's so cute! As soon as he begins to hesitate on the second jump, you can see her digging her heels into him, pushing him into the jump and telling him to behave, and he DID! What a little pro already! She knows him well I'd say. My guess would be 9-10 y/o who has been riding a while. Kinda like my little tootie. When her River gets a little snippy, or pops up, or gets frustrated with her, she gets into him and he behaves too. She's about that size and she's 10 and she's been riding since she was a bun in the oven.