T hank you for all that. I didn't know about the Jannet in 1801. William had sisters Janet and Mary - but I am surprised I haven't come across a Catherine, but as you mention, it doesn't mean to say that there wasn't one whose baptism has not survived.
The Jannet in 1801 is in the list of children of at least two William Moffats in Dumfries posted upthread ^ by
telmark.
However, again, you can't assume that this Jannet's mother was Christian Fraser. The reason for this is that there were, as
telmark pointed out, apparently (at least) two William Moffats, both sons of William Moffats and both baptised in Dumfries within a month of one another - one on 22 February 1810 and one on 21 March 1810. It is conceivable that this is the sam baptism recorded twice, but IMO unlikely because the first one has a middle name and the second one doesn't.
As for the names of William's sisters, that's fine, assuming of course that he is the right William. You would expect him, if his mother was Catherine, to have a sister Catherine, but only if he had more than two sisters, because the tradition is to name the third daughter after the mother.
However it's the names of William's daughters that would help to confirm his identity, and with at least two gaps of 5 years each between children (or a gap of 11 years if Jannet b 1801 isn't the daughter of Christian Fraser) it's impossible to be certain.
It's a bit like trying to do a jigsaw puzzle with a third of the pieces missing!
