I couldn't scan Anne Kermeen als Christian's will for you because it is a very faint copy on A3 from the MM. I am transcribing both this one and husband William Kermeen's 1751 one to send to Brian for his website.
I'm afraid I put them all aside years ago while waiting to make contact again with Tom Kermen.

Several documents refer to John Kermeen as son of both William and Anne (including in William's will) and as he was clearly a younger son I was pondering about that "natural son" until I saw it again in context.

It reads "Item she left to her Son in Law Thos Corkill and to her own Natural Son John Kermeen a Quarter of an Ox betwixt them as a Legacy ~"
With an insert above the line following Thos Corkill: "and his wife Ellinor".

As John is repeatedly referred to elsewhere, including in the same will, just as John Kermeen (as son, brother, etc.), I think this "natural" was written simply to distinguish him from the son in law in that particular clause about shared inheritance.

Sue