I like the idea of Canada, Hong Kong and Seychelles being the ‘Adopted Trio’. All three use to belong to another Country before being taken in by England. The three of them like to hang out and are close to each other.
Canada (Probably the oldest) first helped the Hong Kong get use to life with England when they were young since Canada knew what it was like. He would let HK cuddle Kumajirou and keep him company. In return, HK saw him as a big brother and someone that made him feel safe. Later on Seychelles showed up after Canada and HK grew up (Teens) and they felt that they should be her big brothers and look after her. Since they all had something in common.
Now they have this special bond and when given the chance, they’ll go out together and hang out or stay over. I would like to think that Canada can switch from English, French and Cantonese when talking to the both of them. Especially when trying to talk to them in secret or cracking jokes about someone.
Both Hong Kong and Seychelles have the same name for their capital, Victoria. The capital for BC in Canada is also Victoria.