End of the Spear

I just watched a very moving recreation of a story about how the death of a little boy's father trying to help one of the last warring indigenous tribes in the Rain Forest affected both his life and the tribes. Some wonderful wisdom and heart wrenching trauma in this film. You can view it on hulu and the title is the title of this thread.

i remember this movie, whats crazy is the little boy grew up with the guys who killed his dad,

Yes that's the one but the family were missionaries I believe and lived near the jungle. It's very believable because the little boy wanted to continue his dad's dream of preventing these tribes from being wiped out by government officials. The dad was very aware of the dangers and the little boy too who gave him those three words in their language if he ever got into trouble.