More precious than gold, but cannot be bought,
Can never be sold, only earned if it’s sought,
If it is broken it can still can be mended,
At birth it can’t start nor by death is it ended.
Friendship. It is more precious than gold to have a genuine friend, and true friendship cannot be bought or sold, only earned. When a friendship is broken it can be fixed and infants aren’t able to make friends until they’re older, but death can’t end it. Love doesn’t work as an answer because a friendship requires two people to interact, while parents love their children as soon as they’re born.