Hello,
Found a bit more information on John Foster and Mary Bell. The microfiche I ordered from LDS turned out to be nothing more than what could be found on familysearch!

Mary Bell was christened 28 June 1801 in Hesket-In-The-Forest, Cumberland, England.
Her parents were John Bell b. abt.1762 and Margaret Longrigg b.19 Feb.1767 Wreay By Carlisle, Cumberland.
John Bell and Margaret Longrigg were married 8 Jan. 1795 Hesket-In-The-Forest. Margaret Longrigg's parents were Robert Longrigg and Sarah (unk.) John Bell and Margaret Longrigg had the following children including Mary Bell. There may be other children I didn't find.
Richard Bell chr. 1 Apr. 1798 Hesket-In-The-Forest, Cumberland, England
Mary Bell chr. 28 June 1801 (same as above)
Thomas Bell chr. 6 Jan. 1806 (same) died 22 Feb. 1818 (same)
Sarah Bell chr. 21 July 1807
On familysearch I found children born to Robert Longrigg and Sarah (unk.) all born in Wreay by Carlisle, Cumberland, England.
Robert Longrigg chr. 28 Jan. 1765
Margaret Longrigg chr. 19 Feb.1767
John Longrigg chr. 5 June 1769
Elizabeth Longrigg chr. 13 Jan. 1772
Sarah Longrigg chr. 8 May 1774
William Longrigg chr. 8 Nov. 1776
Thomas Longrigg chr. 5 Sep. 1779
James Longrigg chr. 19 May 1782
and also an Ann Longrigg chr. 21 Jan. 1789 which I am questioning as all the other christenings were stated as being born to parents Robert Longrigg and Sarah (unk.) and on Ann's christening it states her parents as Robert Longrigg and Sarah BELL. I am wondering if the above son, Robert Longrigg chr. 28 Jan. 1765 may possibly be her father and he married a Sarah Bell.
Does anyone have further information on the Longrigg family in Wreay by Carlisle, Cumberland?
Thank-you,
Best Regards,
Denise