William & Polly Johnson 1850 census

I am interested in a family on the 1850 Covington County census, page 133A:

William Johnson - 66, NC
Polly Johnson - 66, SC
Elizabeth Lawrence - 15, AL
Nancy McCormick - 11, AL
William McCormick - 9, AL

You would think that the youngsters with William and Polly were probably their grandchildren? In the household just before them, is the Henry and Mary Ann Hart family.Then in the household just after the Johnsons is the Carr and Nancy Hart family.I wonder if Mary Ann and Nancy were possibly daughters of William and Polly.

I cannot find the Johnsons on the 1860 census anywhere, but Henry and Mary Ann Hart are on the 1860 Conecuh County census.

On the 1870 Conecuh County census, page 170A is the following household:

James Johnson - 54, GA
Susan Johnson - 27, AL
Polly Johnson - 85, NC

James Johnson was my gg-grandfather.His wife Emily died March 1870 (the 1870 Conecuh Mortality Schedule).Susan was one of their 4 daughters.You would think that Polly was probably his mother.

I conjecture that the Polly Johnson, wife of William, in Covington County in 1850 was probably the Polly Johnson with my gg-grandfather on the 1870 Conecuh County census.

Does anyone have any info on this Johnson family?

Ken Johnson
Jackson, MS