re: John Purifoy, d Ala 1839

I am still trying to find proof of the parentage of my John Purifoy, born 1787 Craven co,NC, died 1839 in AL.He married Nancy williams in 1809 in Hancock Co, Ga.Most researchers say John's father was Thomas & his mother Sallie.But I haven't been able to find any proof of this.Can someone help me with this?I haven't worked this line is quite a while so someone may have made a break thru since I've heard anything.