Correct what problem? Everything on this kid is lagging and having him try to pick and choose right now what needs more attention when he is so new to this he actually thought his arms were just leaving everything else behind is ridiculous.
He needs to learn how to have a balanced program from here on out.
His stats listed should have been a sign to most of what stage of development he was at.
Asking him to post a pic confirmed it.
I am not understanding those who think someone like this needs to focus less on a certain muscle group as if he is suffering some huge imbalance.
Also, in the pic posted, he is pressing his arm against the side of his body just in case some of you can't tell the difference.