The most important thing parents have to do is to raise their children to adults without screwing them up. What happens to children especially those under ten, because that’s the most impressionable age, stays with them for the rest of their lives.
My father had two brothers and one day way back in the mists of time there was a fall out. His middle brother fell out with the eldest and from that day on there was no contact between them or their mother. I had cousins that I never knew about and always regretted that because our family was not very big and I had no other cousins. I always thought that family feuds like this are silly and should be solved, until now.
My brother David is ten years younger than me and he fell out with both myself and my son four or five years ago over very little indeed.