He's trying really hard to take care of his son in his time of need and even tried to have him try out pottery as a means of bonding and mental therapy. He was young so he didn't understand why but seeing him for the very last time before he returned 8 years later in a car unaware of his son greeting him and looking forward to playing with him wasn't a very pleasant memory for him at all. He could've handled things better back then but he's definitely doing his best this time I guess. I hope things get better...
Beating his sentiments into one of the mover guys made them all realize how they shouldn't belittle Nomiya like that. His ego impressed them all just like what happened with Nagano.