Originally Posted by
aisleorwindow
Should be OK. The E175s are considerably larger and more comfortable than the CRJ200 which is what the OP is referring to.
I would call AA and explain the situation and see if your father can get a bulkhead seat, or at least a seat near the front of the plane.
And the e175 is almost assuredly going to use a jetbridge gate at both ends. Not as much of a sure thing on a crj.