That is unusual lighting now that you and Kelvin mention it. I haven't doctored the photo except for my normal cropping and levels, and you know me - I don't even dodge or burn. I'm pretty sure this image was taken in the morning, and that's about where the Sun would be (behind K.) at that time.
This area is deeply shaded by a big maple and an oak, and K. is also inside a covered play hut, so it's quite dim except for that light sneaking in. Iso800 @f2.8 and it was still a slow exposure for hand holding. I guess the reflections in her eyes were just the sky behind me? There were no other light sources so I'm at a loss.