He could be a relative, but all of Richard's children are listed in his will and can be found in the "Register of Maryland's Heraldic Families" - I show the following: Richard Jefferson's will was made January 2, 1780. It mentions his wife, Polly (aka Mary), and children Warren, Job, Rhoda (m. Ennis), Elihu, John Richard, Elizabeth, Ede, and Joshua. Places mentioned include: Poplar Island, Poplar, Jefferson's Lot, Hog Quarter, Good Luck, Little Neck, Hutchson's Addition. In 1741 Richard Jefferson received a grant of 253 acres called Poplar Ridge, on Tuskey (probably Turkey) Branch. In 1888, it was the home of Miles Messick, called Pleasant Plain. (Source: De. Hist. Society Genealogy Surname List Card) He purchased 35 acres of land from Edward Wright on June 5, 1711 at Barren Quarter (Delaware) in Nanticoke along Barren Creek. Jefferson received land grants having served in the Colonial Wars, and would eventually accumulate over 1,100 acres of land."
I have no Absolom in my database, but there are many unnamed males for Richard's grandchildren.