Simplify the following text for a Grade 6 native English-speaking person.
Original: When Kullervo is three months old , he is heard uttering vows of revenge and destruction on Untamo 's tribe . Untamo tries three times to have Kullervo killed ( by drowning , fire and hanging ) .
Simplified: In the Kalevala Kullervo 's family is killed by Untamo 's family before Kullervo is born .