PIP. My son used our cable box remote to turn on the TV and cable box. When I went to check on

Question

My son used our cable box remote to turn on the TV and cable box. When I went to check on him he was watching the TV and the picture was small and in the right hand corner. I asked him what had happened and he said he didn't know.

We programmed the cable box remote to work the TV as well. When I asked him what he did he said "I just turned it on." I suspect he may have hit a button that threw the TV setting off. We have tried everything to get it back to normal picture mode but nothing has worked. We even tried restoring the TV's factory settings but that too has not worked.

Please help!