His father was Nathan, from Windsor Co. CT. You can read about Elias' line here:

http://genforum.genealogy.com/pettigrew/messages/1407.html
"Pettegrew brothers: Daniel, David, Nathan; VT & Dearborn Co. IN; 1818-50s."

The following info is given there as well.

Federal census info, from Ancestry.com:

1850: Manchester, Dearborn, Indiana (taken 2 Nov 1850)
(all were indexed as Pettingrew, but clearly were Pettigrew in the census image)
Nathan Pettigrew 57 b. VT, carpenter
Mary Pettigrew 54 b. PA
William Pettigrew 25 b. IN, carpenter
Swithen Pettigrew 1 b. IN (indexed as Surthen. This is William's son.)
Elias Pettigrew 21 b. IN, carpenter
Edward Pettigrew 18 b. IN, farmer (Darius Edward)
Jonathan Pettigrew 16 b. IN, farmer
Rachel Chandler 78 b. PA

1860: Tiskilwa, Bureau, Illinois
Elias N Pettigrew 30 b. IN
Atlanta Pettigrew 22
Eddie Pettigrew 1

1870: Indiantown, Bureau, Illinois
Elias Pettigrew 39
Atlanta Pettigrew 33
Edward Pettigrew 11
Charles Pettigrew 9
Jesse Pettigrew 8
Harry Pettigrew 6
Minnie Pettigrew 4
Jasper Pettigrew 1