Peter Quill's Uncle

History
His sister mothered a child who would become the superhero Star-Lord

Guardians of the Galaxy Vol. 2
Merh Quill's Brother thought his sister was delusional because of her thoughts on his nephew's biological father being from space.

Guardians of the Galaxy
Merh's brother was present when his sister dies of brain cancer

Family

 * Unnamed mother
 * Unnamed father
 * Merh Quill (sister)
 * Peter Quill (nephew)

Appearances

 * Guardians of the Galaxy
 * Guardians of the Galaxy Vol. 2