Eileen: On the 1881 UK census Mary Atkinson is listed as 22 years old (not 17); her sister Selina is 17.

1881 UK census:
Benjamin ATKINSON Head M Male 56 Ireland Hotel Keeper
Catharine ATKINSON Wife M Female 55 Ireland
Mary ATKINSON Daur U Female 22 Castletown, Isle of Man, England Milliner
Jane ATKINSON Daur U Female 20 Douglas, Isle of Man, England Barmaid
Selina ATKINSON Daur U Female 17 Douglas, Isle of Man, England Scholar
Richard ATKINSON Other Male 2 Douglas, Isle of Man, England

1871 UK census:
Name: Mary Atkinson
Age in 1871: 12
Estimated Birth Year: abt 1859
Relation: Daughter
Father's Name: Benjamin
Mother's Name: Catherine
Gender: Female
Where born: Castletown, Isle of Man, Isle of Man
Civil Parish: Conchan
Town: Douglas
County/Island: Isle of Man
Country: Isle of Man
Registration district: Isle Of Man
Sub registration district: F
ED, institution, or vessel: 3
Household schedule number: 116
Household Members: Name Age
Benjamin Atkinson 43
Catherine Atkinson 45
Felina Atkinson 7
Jane Atkinson 10
John Atkinson 16
Mary Atkinson 12

1861 UK census:
Name: Mary Atkinson
Age: 3
Estimated Birth Year: abt 1858
Relation: Daughter
Father's Name: Benjamin
Mother's Name: Cath
Gender: Female
Where born: Castleton, Isle of Man, Isle of Man
Civil Parish or Township: Conchan
County/Island: Isle of Man
Country: Isle of Man
Registration district: Anglesey
Sub registration district: Holyhead
ED, institution, or vessel: 4b
Household schedule number: 232
Household Members: Name Age
Benjamin Atkinson 37
Benjamin Atkinson 61
Cath Atkinson 36
Jane Atkinson 15 Mo
John Atkinson 6
Joseph Atkinson 16
Mary Atkinson 3
Richd Atkinson 12

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