Wendy:I believe David Briggs, Jr.'s 1st wife was Rachel Hathaway 5 (Thos. 4).David & Sybil's children were: Abner b. 18 July, 1754, mar. Betty Strange; James b. 11 July 1759 and Sybil b. 20 Dec. 1761. Therefore I would assume Arnold may have been a son by Rachel but have no info re that.