Thinking about the suggestion of how difficult Gouenji's relationship with his mother death was. He's simply quiet about it, even if that destroyed his family. How he wasn't allowed to grieve properly and how he has no one to talk about it. His father was changed to the core because of that death, and even if he thinks of her, he turned emotionally neglectful to Gouenji, and Yuuka with her accident and all she's been through is simply too young to maybe even remember her mom properly, even when she's just a little copy of her. So Gouenji is in the middle, an uncomfortable place in where he's the only one that is still able to think of her and has no one to talk about it.
If he were to talk about her, I believe the person that Gouenji would feel comfortable talking about his mom has to be Hijikata. In S2, when Gouenji's world came crashing down once again, Hijikata was there to give him not only a place to be safe, but also was the one to constantly push for him to open up and in a way held him together when he could've fall into pieces.
If Gouenji is ever allowed to grieve his mom and talk about her, I'm sure it would be Hijikata asking about her in a manner Gouenji could deal with the pain. Hijikata would be there to lend an ear.
