You mentioned in your post that David's family was listed in the 1850 Rutherford Co, NC index.I do not find them in Rutherford Co. but did find them in Cleveland Co., NC.
Looking at the Allens in Cleveland Co. NC in 1850 lends credence that Larkin Allen was the father of David, James and William who were all of an age to be brothers and sons of Larkin Allen.With so many of the children, grandchildren etc. naming a son Larkin, also lends credence to Larkin Allen being the ancestor. If so, who was Larkin's father?
It also seems much more likely that David's wife's last name was Camp instead of Massie, as there were several Camp families living in Cleveland Co. NC during this time period, including an Abner Camp age 78, who is presumed to be father of Elizabeth Camp who married Champion A. Allen.
Champion and Elizabeth's son David Weldon Allen married Alice Chandler dtr of William Pierce Chandler and Missouri Vasti Gentry.Marshall Champion Allen married Frances Jane Robertson, dtr. of Missouri Vasti Gentry (Chandler) and her second husband Robert Robertson.There were a couple more marriages between these Allen descendants and some of my lines.
What I have been trying to prove is the kinship of this David Allen to Robert Allen,Sr-Elizabeth Walker if any, and to make the connection to my Allen line, which is through Robert Allen, Sr. and Elizabeth Walker.
Allens -1850 census of Cleveland County, NC: Household 671 pg 163 David Allen 53m b. NC occ: farmer? Elizabeth Allen 54f Mary 24f Lydia 22f David 21m Labon? 19m Champion? 17m William 15m Davis? 13m Rebecca 11f Perry? 7m
Household 672 pg 163 Elbert Allen 30m b. NC occ: farmer? Almedia? 27f Marcus A 6m Wiliam 5m Larkin 3m Rosalind? 2f David 1m
Household 674 pg 163 Clarke 31m b. NC occ: School Master Agnes 27f Martha J. 6f Elizabeth 4f Reynold? 11/12 m Narcipeus Heickes? Narcissus Hicks
Household 675 pg 163 Abner Allen 26m b. NC occ: farmer? Judea? 26f Elizabeth F. 4f Walter A. 1m
Household 684 pg 164 James Allen 53m b. NC occ: farmer
Household 702 pg 165 William Allen 62m b. NC Mary 58f William 26?m Sally Spake 23f Adam Spake 20m
Household 1084 pg 189 Larkin Allen 86?m b. NC occ: farmer? Sally 36f Eliza 12d Joseph 7m