Grace Colt (Dundas) - Grace Colt's Parentage

I am the 6th great granddaughter of Grace Colt and have discovered that her mother was actually her father's second wife, Jean Grant, and not his first wife, Henrietta Baillie. This is validated firstly by the site http://www.dundasfamily.co.uk which lists Grace's mother as Jean Grant. Also, Henrietta died in 1755, whilst Grace is thought to have been born around 1760. Finally, Grace's name was actually Grizel, however she was referred to as Grace. Grizel was a popular family name in Jean Grant's family. Her mother was named Grizel Millar, and Grizel Millar's father's mother was also called Grizel. This is the strongest evidence supporting Jean Grant being Grace's mother, as this would mean she named her daughter after her mother and great-grandmother.