is he s/o William + Martha Brown - william is indicated as 'P' (?pensioner ?army) sharing a property in malew Street (with Jane Dinwoody) - all shown as born Ireland - can't find in 1851 but Martha is there with son Wm (age 8 - ? the wm age 1in 1841 - a widowed 'plain sewer' still in malew Street Castletown