This source is about the American revolution in the anime hetalia, the characters are United States & United Kingdom.
The brotherly relationship between England and America changed irreversibly when an older America declared to England that he was no longer his little brother and wanted to be independent. England, unwilling to let this happen, managed to overpower America but ultimately found himself unable to shoot his former colony. When England collapsed into tears at America's feet. America looked down and remembered when he looked up to England as a child; he comments that England used to be so big.