Please explain why you think that! You literally just see her sitting on a tube, fall over while shrieking and then start drowning because she probably swallowed water the wrong way while shrieking and falling into the water. At that point, it's game over, doesn't matter how good a swimmer she is because she's literally not in control of her body.
Edit: to be clear, I agree that she's very unlikely to be a local swim champion or something. What I am claiming is that even a standard knows-how-to-swim 9 year old can start drowning like that.
Yea but that's the difference between knows-how-to-swim and being a strong swimmer. If she was a strong swimmer she would be in control of her body after something as trivial as flipping out of a tube.
Edit: to be clear, I agree that she's very unlikely to be a local swim champion or something. What I am claiming is that even a standard knows-how-to-swim 9 year old can start drowning like that.