I'm afraid I don't have any info on children for Abijah & Submit. I descend from a sister of his father Joseph, so I haven't followed his line in great detail. I haven't seen the original Rockingham records, only printed copies, so I don't know what the actual spelling of his name is. I have found that in both his grandfathers & uncles case, the hand written records have Ahijah, but when it is transcribed into secondary sources the "h" is quite often misread as a "b". According to a book "Who's Who in the Bible" Ahijah & Abijah are names of different people and not variations of the same name. A close check of the original VT & OH records would need to be done to see which was the actual spelling for your man.