I've seen a similar version of this in people quite close to me who've had a narcissistic and neglectful family. Sometimes when I was younger I'd ask my mother about a happy memory from her childhood. She would reply "why are you asking about the past? it's a long time ago, how am I supposed to remember?" It's a defence mechanism of sorts. It was only until she opened up to me about her childhood did everything make sense. She's like this with outsiders, though, very closed off.

Her mindset, which I see is similar to the Roy siblings sometimes is "it was in the past, it was a long time ago, I'm over it, so what?" etc. They don't want to talk about it. When my mother does decide to talk about her childhood freely, her sentences sometimes trail off and her tone becomes uneasy. It's a signal that she doesn't want to talk about it anymore so I don't press her to talk and I switch the conversation to one of her interests.

Sometimes these questions are triggering. Roman would be good in an interview about anything apart from his personal life. Therapy can never fully undo the damage Logan has done to his children.