Simplify the following text for a Grade 16 native English-speaking person.
Original: His brother was the writer Aldous Huxley , and his half-brother a fellow biologist and Nobel laureate , Andrew Huxley ; his father was writer and editor Leonard Huxley ; and his paternal grandfather was Thomas Henry Huxley , a friend and supporter of Charles Darwin and proponent of evolution .
Simplified: His brother was the writer Aldous Huxley , and his half-brother , a fellow biologist and Nobel laureate , Andrew Huxley ; and his paternal grandfather was Thomas Henry Huxley , a friend and supporter of Charles Darwin and proponent of evolution .