I have a Joseph Flack born 1810 (1880 census shows him as 70 years old) who was married to Rebecca unknown. They had a son named Simon. Joseph's daughter Rebecca is in my line but I do know she had a brother who married a Hannah Nicholson and they had a son they named Simon. I'm not sure when the family came here but all of the above are buried here. Joseph applied for naturalization in 1845.
I don't think this is the person you are looking for but I'm wondering if my Joseph could have had a brother named Simon. I have to wait until I can get to the county they lived in so I can access Joseph's naturalization papers. I do know they came from England because of the same 1880 census that shows he was born in England as were his parents, his son Simon and daugher Rebecca. They had another brother whose name could be James. I'll have to look that up.