My first impression was, "whoa, too much noise reduction." But when I look at the camera exif data, I don't understand why there would have been any noise. So I don't understand why she looks so plastic. I think she is a very cute girl, and you captured a nice candid, but something didn't work out in the processing.
Here is what I like about the photo. Good rich colors and a nice creamy background.
I like the intent, the dedication of the cupcake of the child.
Some things to consider in the future.
Slight different Point of View. It's a tough angle you are working with here as such it makes it difficult to connection between the cupcake and the girl. A front, low end shot might have been better...perhaps. But you do some glimpses of a wonderful expression there, just need to capitalize on it more.
Post - Looking at the equipment you used and your setting not sure what happened. Seems slightly wavy, almost like extreme noise reduction which you should need at your settings?
The initial impression from the thumb is pretty good, but it doesn't hold up enlarged which I believe hurt you here.
It's a good candid.
One last note, not sure if the person in the photo is in relation, but sometimes our hearts follow the photo too much. I have happened this too many times and an extra pair of subjective eyes often helps.
No worries, I have had 3 browns myself. Just keep at it. Everything is a learning experience, good and bad shots included.
Extreme zoom, extreme crop, and noise reduction detract from the moment captured. This feels just like a snap at a soccer field, and less an image you set out to take for the challenge. Child is cute, but the photo itself doesn't work with her cuteness and it feels like it was entered just to have something to refresh during the week.
A pretty good candid, but there are some digitial artifacts that detract from the presentation. On my monitor, her hair appears to be in little blocks - not sure what's causing that.