In the April to June 1841 birth index,
Eliza Symondson, Pancras district, London. Middlesex, volume 1, page 321
In the 1841 census civil parish St. Pancras, Middlesex, Ossulstone (Holborn Division) hundred, Tottenham sub district Gufoe? Street.
Phillip Symondson, age 30, born Middlesex, no occupation listed.
Sarah Symondson age 20, born in Middlesex.
Clara Symondson, age 2 born in Middlesex.
Eliza Symondson, age 6 weeks, born in Middlesex.
Listed before them are James Haily, age 50. Mary Haily, age 50. John and Anne Edwards, ages 20. John Edwards age 6 months.
In the 1851 census Clerkenwell civil parish, St. Philip ecclesiastical parish, sub district Amwell, Middlesex, 12 Noble Street.
Philip Symonds, head, married, age 42, Bell founder Journeyman, born St. Giles Middlesex.
Wife Sarah Symonds, age 33, dress maker, born ???? Middlesex.
Daughter Clara Symonds, age 12, born St. Pancras, Middlesex.
Daughter
Eliza Symonds, age 10, born St Pancras.
Son Philip Symonds, age 3, born Clerkenwell, Middlesex.
In the 1861 census Shoreditch civil parish, Shoreditch St Leonard ecclesiastical parish, Middlesex, Hoxton New Town sub district 47 Union? Buildings.
Henry Harrison, head, married, age 23, Porter Jobbing, born Tooting Surrey.
Wife Clara Harrison, age 22, Brush Drawer, born St. Pancras.
Visitor,
Elisa Symondson, unmarried, age 20, born St. Pancras.
Son Henry Harrison, age 3 months, born St. Lukes.
In the 1871 census civil parish of St Pancras, Christchurch ecclesiastical parish, London, Pancras registration district, Camden Town sub district, 3 Suffolk Street East.
Sarah Symondson, head. widow, age 53, on parish relief, born Pancras.
Daughter
Elisa Symondson, age 26 [should this be 30?], unmarried, ironer, born Pancras.
The following is a possible lead to follow up.
from
https://www.rootsweb.ancestry.com/~nzlscant/bdm1881.htmTimaru Herald - South Canterbury’s newspaper
February 1881, Marriages
BLACKMORE - SYMONDSON - At the Congregational Church, on January 29th, by the Rev. Henry Williams, John Blackmore, of North street, Timaru, to
Eliza Symondson, late of Christchurch and formerly of New Road, Kings Cross, London.
Timaru Herald, July 1885, Deaths
BLACKMORE - On the 1st July, the wife of J.D. Blackmore, Makikihi, aged 44 years. [If this is the John Blackmore above, and this his is wife Eliza, the age is a match to the Eliza Symondson]
Also possibly connected. In the 2 April 1873 Timaru Herald
Port of Timaru, arrived April 1 -- Maori, s.s., 118 tons, Malcolm from Lyttleton. passengers, Missis LeCren(2),
Miss Symondson, Miss White, and 6 in steerage.
[Since Kings Cross is very near St Pancras, it adds credibility to the possibility. Also an Emma Symondson married in 1871 also in Timaru New Zealand, Moses Jonas, they had 9 children.]