There is a Aaron Eliphalet[Lafe] Kniffen. He marred twice to Jenny Etta DARNELL & to Permelia Ann PENROD. Him $ Jenny had 4 kids. Him & Permelia had 9 kids. My grandma's dad was one of the 9 kids George Lester Niffen. He had a twin sister that died at birth.
The "K" was dropped from Kniffen after 1900 and the Niffens were born; Beginning with the marriage to Permelia Ann Penrod, the name became; Niffen.