Simplify the following text for a Grade 4 native English-speaking person.
Original: This time , the BÃ b and his companion were killed . In the BÃ bÃ â `` BahÃ ' Ã tradition , the failure of the first firing squad to kill the BÃ b is believed to have been a miracle .
Simplified: After he started the religion , he changed his name to BÃ b. People who believe in the BÃ b are called BÃ bÃ s , and they believe that the BÃ b was a prophet .