He has a layover in atlanta which is stressfull for anyone but its only 52 minutes and he has never been on a plane or in an airport, can someone meet him off the plane and lead him to his next gate so he doesnt get lost and miss his flight??
If your family member is elderly or if he is a minor, then you can arrange some options for him. But if he is a fully functional adult, then he is pretty much on his own.
Atlanta is not that difficult of an airport to navigate, but it can be crowded. Assuming he is flying Delta, they usually have someone at the gate to direct passengers to their next flight and they would be happy to give him detail instructions of getting to his next gate. And there are often information people at the train stations to assist people with finding their way.
Personally I would have booked him flights with a longer layover, as 52 minutes is tight, but still do-able.