The only thing, one might wish the bubbles were brighter. The light on her is just right. The background is appropriately dark and blurred. It's a great photo of the innocence and joy of a kid making bubbles. Kids, worldwide, love doing this, little bubbles, joining them into bigger bubbles, and so on. Maybe it's not just the idea of making something, but of making something that literally floats in the air, like people might imagine of a spirit.
Very nice child portrait. Beautiful colors and great skintone. Composition could have been stronger if there was a little more space to the left (or alternative: a tighter crop on the right side).