I looked in the Coffin book by Louis Coffin and it doesn't have any more info than you already have. It just says that Lydia married James Anthony son of James of North Carolina and that she was born 1735. Richard Coffin her father was son of John and Hope (his 3rd wife). Interestingly it mentions that their son Daniel Coffin who was born sometime after 1719 was killed by a whale on Sept. 9, 1745.There might be some history about that in the annals of Nantucket.Might be worth checking in to. Good Luck on your searching.If your Lydia and her husband went to North Carolina, check Henshaw's Quaker volumes.Many of the Coffin's who went to NC and OH were Quakers.This might be where you'll find them.Any good library should have copies of these volumes.