Not sure how your nephew managed to erase the camera from their iPhone when the camera is not a delete-able app. You may need to restore the device to see if that helps or contact tech support.
That bit of information would have been helpful sooner if you included it in your original post.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
I found out after I went to the apple store and saw ways to fix my issue.
I didn't know my nephew had turn on the restrictions until I read that that could be an issue.
Sent from my iPhone