<Table> <Tr> <Th_colspan="2"> Fox Mulder </Th> </Tr> <Tr> <Td_colspan="2"> The X-Files character </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> First appearance </Th> <Td> "Pilot" (September 10, 1993) </Td> </Tr> <Tr> <Th> Portrayed by </Th> <Td> David Duchovny </Td> </Tr> <Tr> <Th> City </Th> <Td> Washington, D.C. </Td> </Tr> <Tr> <Th_colspan="2"> Information </Th> </Tr> <Tr> <Th> Occupation </Th> <Td> FBI Special Agent </Td> </Tr> <Tr> <Th> Family </Th> <Td> The Smoking Man (biological father) Teena Mulder (mother) Bill Mulder (legal father) Jeffrey Spender (paternal half - brother) Samantha Mulder (maternal half - sister) William Scully (son) Unborn Child </Td> </Tr> <Tr> <Th> Partners </Th> <Td> Dana Scully </Td> </Tr> <Tr> <Th> Affiliations </Th> <Td> John Doggett Monica Reyes Walter Skinner The Lone Gunmen </Td> </Tr> <Tr> <Th> Duration </Th> <Td> 1993--2002, 2008, 2016, 2018--</Td> </Tr> <Tr> <Th> Seasons </Th> <Td> 1 2 3 4 5 6 7 8 9 10 11 </Td> </Tr> <Tr> <Th> Films </Th> <Td> The X-Files, The X-Files: I Want to Believe </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Fox Mulder </Th> </Tr>

Who is mulder's father on the x files