I have tried in vain for the last 2 years to piece together Rachel's origins. Based on the facts, there is no doubt in my mind that Rachel is the daughter of Thomas Vincent and Chloe Dell. Rachel first surfaces in the historical record in 1850, married to Marcus Wilds (Velt) and living in Lewiston, NY, with two children, the oldest of which is only 1. Marcus immigrated from Germany in the 1840's. In those days one never travelled too far to find a spouse, there is no doubt that she would have been close to him. At the time of the 1850 census he was listed as a laborer, and being based in Lewiston, there is no doubt he worked on the first Niagara Suspension bridge or the Welland Canal, both being worked on at the time. Extensive labor was required both and the recent wave of immigrants filled the bill perfectly. I searched the historical record for any mention of a Vincent family in Ontario. The only family that fits the bill were from Welland County, Willoughby township. They were Thomas and Chloe Vincent. Thomas and Chloe were both born in the Niagara district of Canada, Thomas in 1797 and Chloe in 1800. They had a steady flow of children through the mid to late 20's, with a notable exception of 1827, Rachel's birth year. My theory is Rachel indeed met Marcus while he was working on the bridge, based on my data Rachel was pregnant by 1847 at the age of 20. She ran off with Marcus to Lewiston and was disowned by her family for getting pregnant and marrying a poor immigrant. Rachel came from hearty loyalist stock and would have shunned her association with Marcus, thus the absence of any record of her. There is really no other explanation, Marcus' English was poor and there is no way he travelled too far inland when there was work aplenty in Lewiston. Rachel had to have come from Welland County. Her death certificate lists Pushlinch township as her birthplace, but at her birth there was nothing there. Guelph wasn't establish until 1828.
Well that's my theory.