For birds, siblinghood can be a matter of life or death
Some birds kill their siblings soon after hatching. Other birds spend their whole lives with their siblings and will even risk their lives to help each other.
siblinghood
How two good friends became sworn siblings — with the revival of an ancient ritual
Thousands of years ago, there was a ceremony to bind close friends together as sworn siblings. Could the practice be resurrected today to strengthen modern friendships? Two women did just that.