Looking for Eliza Elizabeth Fisher Born London C1827

Eliza married William Worledge RESTELL in 1848 at Hillingdon, Middlesex. They had several daughters, one of whom was my gt grandmother, Emily Maria RESTELL, and one son who died in infancy. I think I have found Eliza as a child on the 1841 census as the only daughter of John and Elizabeth Fisher but I cannot find her birth record or any records of her parents. I would love to be able to go further back in her family.