We are going to have this thread as a project, where you can post and image as it came out of the camera as before and what you did to if as an after. You would need to briefly explain what you did to arrive at the final image.
This is not a discussion in ethics or what should be done. Simply, what CAN be done with the help of software and it is meant to instruct and help those who are interested in learning.
Please try to post the two images together in one image not exceeding 800 pixels on the longest side.
Here is the first, a Pelican landing I took in San Diego. I liked the landing pose, but the shadow of the head in the wing was bothersome.
This does not reflect my usual routine and is only meant as an educational example.
I selected the opposite wing, the pa\rt closest to the body, by quick mask. You can use whatever selection method you are familiar with.
Copied and pasted over the shadow. Edit>Transform>Flip horizontally and now all I had to do is reduce the opacity to place it as close to the original as possible. If it's not consistent, you can use the Edit<Transform>DIstort command, using the Warp option (on the Tool bar on top. After it is placed as you want it, create a layer mask and paint black with the brush to clean the parts you don't want. White will paint them back.