It sounds strange to you, dear @exyle, I have relatives and cousins that I do not know, even living in the same city, but that is because everyone has their own occupations and they watch their things, and you will be surprised, we only see each other when a relative leaves this land, it is when someone dies, it is the only way, and it is sad because the family is very big.
In your case, it's good that even if you do not know your uncle's children, it's good to know that they meet on fun occasions and in a good family exchange, and more on the boat, how good that is. Happy day dear @exyle.