They are weren't traumatized at a young age they were traumatized when they were around 20 years old mentally. So it's like they still are able to trust in people because their mentality back when they were mentally younger were probably able to trust strangers to a certain degree. If they were mentally abuse at a young age you are correct they would be in a worse mental position then they are now. A lot depends on a person's childhood.
Still early adulthood tramatizing is still a thing and can last the rest of your life my great uncle who is 90 only spent 4years(in his early 20s) in the military still has major ptsd
Some adults can handle that kind of stress better than others
Yeah adult mental abuse and other traumas exist so it's hard to pin point on why they may or may not trust him. I'm just saying let's take their mental age into account as a possible reason.
Tru
It is very difficult to write about traumatized people, they trust very slowly in someone and they expect to be betrayed by that person at any moment. But I'm a little confused about twins.
I understand why they don't trust their new family and siblings, even though one sibling protects them and that weakens him. They refused to be in a huge party with strangers, that's awesome. It would be interesting for them to be triggered by women.
But
Why they trust duke so much? That man didn't lift a finger for them. Only his son told a story of the past empress, but I don't think that's such a strong reason to trust the man, given that they were attacked in the garden, they should be a little paranoid about strangers, but when the duke introduced a stranger to be their servant, none of them have a problem with it.
It doesn't matter that the boy is illegitimate, he falls in the strangers' category and the mind should yell that this isn't right, this happens to me, even if I meet a nice person, my mind screams at me that I'm not safe, that the person is doubtful, "I would be stupid to believe this", even my body reject strangers, why the twins' minds are so quiet?
So duke did something for them to trust him? I don't know, he saved them from a fake attack to induce them that they are safe around him?