Sometimes it's the spontaneous situations that tell the true story. You captured the something that could never have been posed. Great shoot, an instant . While the lighting is magnificent and the joy on her face is contagious, I think the cap is what makes the entire scene work.
I love the candid fun to this. She's clearly so relaxed and just laughing and chatting. Her pose is nice, very fresh and youthful with legs wide spread and forearms on knees like that. I think it really work compositionally to have the bend of her right elbow echoed in reverse in the bend of her left knee. Very nice lighting. You've set off her skin and hair very well. I enjoy the very minimalistic nature of her makeup. She's gorgeous, and she barely needs any color at all.