I wanna beat those siblings up! Nora is right what use is there regretting it now when you...

fr!!!!

You're not wrong, but you're forgetting that they were all children. None of them, not even shuli knew how to act in different situations, thus creating a divide between them. What's different in the new timeline is that shuli was mentally older and more mature, thus knowing how to handle the situation better. Plus she knew them better and that probably gave her better emotional tools to improve their bond. In the previous timeline they were all equally immature. I'm not saying that their actions were correct. I'm saying that they were understandable.

Yeah they were younger so at first that was understandable but they had time, lots of time to make it up to her. Jeremy was old enough to get married so must have spent around 10 years together.
But the thing is, the siblings did realize that Shuli is a good person and that she was just trying to help but I guess they were just too proud and 'shy' to admit it and try being nice.

Again, there are plenty of adults who are even more immature and don't know how to apologize or admit their mistakes. Remember, they WERE planning on making up with her. They had a grand plan for how they were going to call her mom and make amends. The timing just wasn't right and you can't really hold that against them, because how were they supposed to predict that she would get MURDERED. It's not like they suddenly realized how much she meant to them when she died. Furthermore, they're orphan nobles. how many mature adult role models do you think they had? Even the most amicable and honest noble they know was a shit father.