This may be them in 1871;
1871 Census
1 New Terrace,
Ffestiniog, Merionethshire, Wales
Lewis PARRY, 39, Head, Mar, Slate Quarrier, born Llandegai, Caernarfonshire
Jane, 39, Wife, Mar
Richard, 16
David, 14
WILLIAM, 12, Son, born Bethesda, Caernarfonshire
Ellen, 10
Joseph, 8
Edward, 5
Mary Cathe, 3 weeks
3 Younger Children are born Ffestiniog, Merionethshire
1851 Lewis seems to be with Parents WILLIAM/ANN, born c 1831 Llandegai, Caernarvonshire;
Siblings, William Parry 15, Ann Parry 10, Edward Parry 9, John Parry 7, Elisabeth Parry 5, Daniel Parry 3, Henry Parry 1
1841 Census
William Parry 31
Anne Parry 27
Lewis Parry 10
David Parry 8
William Parry 5
Anne Parry 5 Mo
David Evans 65