What other information do you have to confirm that this might be the right family?
1901 census RG13 225 folio 24
23 Duncan Square Hackney  London   
Joseph Smith 49 Hackney, London,  Head Married Boot finisher
Sarah Smith 42 Bethnal Green, London,  Wife Married
Sarah Smith 22  Bethnal Green, London,  Daughter  Boot Machinist
Alice Smith 19  Bethnal Green, London,  Daughter Boot Machinist 
Frederick Smith 15 Bethnal Green, London,  Son Van Guard
Alfred Smith  13 Bethnal Green, London,  Son  
Elizabeth Smith  11  Hackney, London,  Daughter  
Florence Smith  8  Hackney, London, Daughter  
1891 census RG12 97
31 Duncan Square Hackney  London   
Joseph Smith 38 Bethnal Green, London,  Head Married Bootfinisher
Sarah Smith 32 Bethnal Green, London, Wife  Married
Sarah Smith 12 Bethnal Green, London, Daughter  
Joseph Smith  10 Bethnal Green, London, Son  
Alice Smith 8 Bethnal Green, London,  Daughter  
Fredk Smith 5 Bethnal Green, London, Son    
Alfred Smith 3 Bethnal Green, London,  Son  
Elizth Smith ½ Bethnal Green, London,  Daughter  
1881 census RG11 428 folio 31
14 Blyth Street Bethnal Green  London 
Joseph Smith 27 Loughborough, Leicestershire, Head Married Bootfinisher
Sarah Smith  21 Bethnal Green, Middlesex,  Wife Married Bootfinisher's wife    
Sarah Smith 1 Bethnal Green, Middlesex,  Daughter  
Joseph Smith 3mths  Bethnal Green, Middlesex,  Son  
Regards
Valda