Just a thought on Marguarite, Roberts mother was Margaret, so possibly named after her but with a 'theatrical flourish' ?
1 Apr 1866 Cathedral & Parish Church, Manchester
Robert s/o William (Shoemaker) & Margaret Owen of Manchester. Born 7 Jan 1866
1871 2 Campbells Court, Elizabeth Street, Manchester
William  Owen  29  Head  Manchester  Shoe Maker    
Margaret  Owen  27  Wife  Manchester, Cotton Operative    
Robert  Owen  5  1866 Son  Manchester  Scholar   
1881 61 Pott Street, Manchester
Margaret  Owen  39  Head  Wid  Manchester Factory Operative    
Robert  Owen  15  Son  Manchester  Glass House (Glass Blower?)