I don't know what his father does in the military.
Whether he runs the commissary on a LST or plays pacman with spooky.
When I was in they did not allow me to talk (because of what I was doing)
I sent letters which were mailed weekly or monthly and any electronic communication was in writing through official correspondence meaning I wrote it, was read by the military and sent in a general mailbox.
When my mother died (I was overseas on tour) I was removed from the "environment" and sent to a pastor who read me a one line email. Mother died . message may upset enlisted personnel.
The enemy is listening people. Yep you can read this message anywhere in the world with internet access. They , the enemy try to figure out and time the military movement so they, the enemy can time the best time to attack. They even want to blow up the computer or find the family so they can email or send threats in some way. Anything to upset the USA. That is the likey reason why the military father was not able to plan his exact time to call.
With this said I would think the school administration would support the Assist prin decision to let this child get a call from Dad.
Too bad an attorney doesn't litigate this out.
For all you people out there who believe the military should not be honored,
you should not take freedom so lightly.