Simplify the following text for a Grade 7 native English-speaking person.
Original: His son Ã Ã rarinn EldjÃ rn is one of Iceland 's most popular authors , specializing in short stories , but also writing poetry and an occasional novel . His daughter SigrÃ n EldjÃ rn is also an author and illustrator of several children 's books .
Simplified: His son is Ã Ã rarinn EldjÃ rn who is a popular author in Iceland and his daughter SigrÃ n EldjÃ rn is also an author .