1826 Elizabeth Thomas was baptised at 4 March 1826 . She was born at the Old Factory in Upper Corris and baptised at Talyllyn Church. The daughter of Rees's sister Elinor was baptised on the same day and she also was named Elizabeth.
1841 census. Elizabeth had left home by now. Elizabeth, now fifteen, was likely to be working as a domestic servant elsewhere. There is an 1841 record of an Elizabeth Thomas aged fifteen being employed by Hugh Jones, a farmer at Tycroes in Llanfihangel Y Pennant. In addition to the same name and age, other circumstantial support for thinking this is our Elizabeth Thomas is that Rees's Elizabeth gave birth to an illegitimate daughter, baptised Margaret Jones in October 1846. Hugh Jones the farmer had an eligible agricultural labourer five years older than Elizabeth who was also named Hugh Jones. Sadly Margaret Jones died in January 1848.
however there is a second "Elizabeth Thomas, age 15, servant listed in Llanfihangel-y-Pennant
So she could be either.
1851 census. Probably this is her entry. For what its worth, there is a William Jones, grandson of the head of household, age 27 living there too.
1851 Ancestry public tree gives marriage to Jonas Francis 1851 on 20th June at St Mary's Church, Talyllyn, Merionethshire (marriage cert June Dolgellau 27 269) . And died: 25. Nov. 1895 20. Red Lion St, Towyn, Merionethshire, Wales
1861 census - She is married to Jonas Francis (who has been married before, and is listed in 1841 as married to Mary Plus their 1 year old daughter Jane)