Elizabeth Pitt B 1801 England M Daniel Prince B 1794 D 1850 Child Priscilla B 1826 Who Married George Duke Surrey and Emigrated to New Zealand with...

Does anyone have Elizabeth's parents, predecessors etc. on a family tree ? Who is Elizabeth PITT (i.e.,, is she of William Pitt's family perhance ?)
Family lore says she went as Governess to India (don't know year, presumably after being widowed in 1850) for Sir .. KNATCHBULL.
A family member has the sampler she made in 1809, as a child.