Simplify the following text for a Grade 8 native English-speaking person.
Original: Sean Taro Ono Lennon ( , born October 9 , 1975 ) is an American singer , songwriter , musician , guitarist and actor . He is the only son of John Lennon and Yoko Ono .
Simplified: Sean Taro Ono Lennon ( born October 9 1975 ) is the son of John Lennon and his second wife Yoko Ono .