Look at the 1850 census for Choctaw County. Ala. Jonathan Dodd(Dod) is listed with wife, Lusinda (Martin)wed #1 McDowell,#2 Jonathan Dodd. Sons listed as William & Henry Dodd but in 1860 these two men are in Clarke Co. Alabama as William McDowell and Henry McDowell. Old Jonathan Dodd is dead by 1860 census and the stepsons are using their genetic father's name and not the Dodd name of the stepfather. Two Dodd sons Ashley Haywood Dodd and James Riley Dodd are in the 1850 census also. Ashley has a sisterinlaw-Loucendia Read(Reed) living with him and his wife Lucy CAVE Dodd. He and James took both their families and went to TX by 1860. Dodd women wed in Clarke Co to family's Heaton and Curtis.
There is a Dugal Dodd age 14 living with Lousinda Dodd, widow, in Clarke Co. Ala 1860. He is not found in 1870 census. Pearl Dodd could be his child?
There is a HOLCOMB researcher who is direct to this bunch of McDowells. I don't have an e-mail for her. This family is posted on the LDS (familysearch.org) website.
Have you checked !880 census and 1900, 1910 census up through 1930. If the family McDowell/Dodd came after 1900? You should be able to find them on census. Names are given since 1850. 1880 census is free on line in several places. Google works also. I sincerely wish you success, Judy