It may be the shiftlock, next time it happens, tell her to let go of the key, push the selector a little harder into park, then push the brake pedal down very hard, and try to remove the key. (I'm guessing this is an automatic?). Does the key ever have trouble in the door locks? Does she ever have to jiggle the key in the ignition? If so, I'd take the care to your Honda dealership and have them make a new key from the vehicle VIN.