I can't find baptism of Esther Jones Pearse in Tavistock, but there is a baptism for John son of Edmund and Grace Pearse on 26 Feb 1815 (born 30 Jan 1815) at Tavistock Wesleyan. In 1851 there is Edmund Pearse born Launceston Cornwall abt 1788 occupation surgeon, wife Grace b Tavistock abt 1793, and daughter Maria W b abt 1830 Tavistock. In 1841, Edmund and Grace have John (1815) also surgeon, Mary Crabb? Pearse 1816 (spinster written but crossed out), Sarah Kerswill 1837, Grace Edmunda Pearse 1822, Mary Ann Hall Pearse 1830, Thomas Franklin Pearse 1832. All except Edmund born in county. The position of 4 year old Sarah Kerswill in the list is odd.
I think Esther is a governess in 1841.
I think the John Pearse who married Eliza Brown was the son of George Pearse and Grace Couch. George was born in Cornwall and would be contemporary of Edmund. Could they be brothers?