Simplify the following text for a Grade 11 native English-speaking person.
Original: They have been named Romulus and Remus ( the formal names are ( 87 ) Sylvia I Romulus and ( 87 ) Sylvia II Remus , respectively ) , after the children of the mythological Rhea Silvia .
Simplified: They have been named Romulus and Remus ( ( 87 ) Sylvia I Romulus and ( 87 ) Sylvia II Remus ) , after the children of the mythological Rhea Silvia .