Benjamin Robertshaw Born Circa 1783 Married Sarah Harrison at Grappenhall IN 1806 Benjamin was a Potter Who Appears IN Liverpool IN 1807 Had 3 Sons...

Can't find his baptism and he died pre the 1841 Census. Y37 DNA test by my male line cousin has revealed a very close 1 mutation match with a direct descendant of William Robertshaw, b. 1869 in Manchester, but he could not be Benjamin's father due to his date of birth? Any suggestions for further research?