It undoubtedly is the same family - Jessie mentions losing the baby too in the letters (if you are feeling depressed you might hold off reading them). There is a possibility that there are more letters at my aunts house and I am trying to get my cousin to check on that.
The surname is Lees not Lee as I mentioned (I went back to my genealogy folder). John Lees was the brother of my dad's grandmother Elizabeth Hanson (nee Lees) - my dad still remembers her. In the letters there are references to Phoebe and Bertha - they were great aunts who I remember very well.
The children of John Lees and Mary Jane Lees appear to have been Frances (Fannie), Ada, Emily, Jessie and Joseph. I am sure any descendant of Jessie would love to see these letters and I know an uncle on that side of the family has traced the Lees family back aways.
I will email the scans of the letters - probably in groups as they are hi-res for readability.