for Nicole - does my bum look big in this?

I have made this as part of a circle of friends thing for Nicole, to add to a book she is making.
I downloaded this image from someone's blog. and now I can't remember who. and I really want to credit the person it's from. I feel really bad for using it and not crediting it to them. so if anyone recognises it please let me know. I'd be really grateful.

edited to say:
Thank you Carrie. I now know where the image is from. Thank you Nancy Dooren, for the marvellous image. I hope you like what I did with it.