
SPOILER
Do forgive me coz I just remember that it was not the queen who visited their estate but the concubine, the 2nd prince, and the 1st princess. The reason they went there in not due to the coup detat but because the concubine wants to find people who appreciate her beauty, like when she was still not married to the king. Because according to her she is not being looked at or appreciate her beauty due to the black hair her children has. But don't think of her as a bad peron, she just have a bad reputation due to some misunderstanding and the tanaka family will help her but they will end up with a bad reputation too. Stay tuned for more details about it. ε=ε=(ノ≧∇≦)ノ
To answer your question/concern, im not entirely sure whether if there territory is the safest. Because i didnt get to finished reading the novel due to my work( ̄へ ̄). All I can say it that the barrier surrounding the entire kingdom is getting weaker

What ,appreciate her beauty?imao well for some might find the concubine irritating and arrogant,specifically is she whas only to find someone who appreciate her beauty,but there are some also like the tanaka family who understand her too,imao they are even being misundstand too just because they help the concubine,though i understand her concern whats wrong for having black hair ?duh theres nothing wrong in it and why is it they always says those who are having black hair mor eyes ,or red hair and red eyes are evil!duh i find it very irritating and annoying i doubt that if your reincarnate in anotherworld and born with either blair hair and brown eyes they still look bad on them,for some reason i found out that most royalty and nobles consist of blond hair ,silver platinum hair red hair or eyes,i think most of the author are fascinated by a blond hair the most and rest was just the choice !
the fathers brother looks like trouble