Last time we were in ATL
we arrived from CUN
at 5:20PM-ish and connecting to our 7:20PM flight to EWR
. Fortunately, we were the only flight that arrived at Concourse E so the immigration process was painless. We transfered to Concourse B which was a bit of a hike and ride on the tram, got at the Concourse B, had a quick bite and boarding was just about to begin. Keep in my mind that it was off hours and we just made it on-time, as sw733 mentioned, 2PM is the rush hour in ATL
, so I guess it's a little bit tight considering you also have a kid in your hands.
It's a cultural thing.