Jane, I'm now waiting to hear from TNA as to how I, an American, can pay for a copy of Isaac's will. I don't know if my credit card will work in England.
I filled out a free family tree at Ancestry, but I got nothing except notices that to find out more about the possible matches, I'd have to pay. If I had the money to do so, I would, but it's out of the question right now.
I've emailed the St. Louis Public Library in St. Louis, Missouri for James's immigration date. The Library offers such look-ups, even for immigrants arriving in states other than Missouri. It could take several weeks to get the information, but I think knowing when James emigrated from England could be very helpful.
What an awful tragedy about Isaac's daughter Ellen and her husband Henry dying as the result of a fire! Glad the Milns children survived, but how sad about their parents.
So, it appears that S. Africa was indeed in the picture. Interesting!
I think I should probably wait to see what Isaac's will says regarding heirs before I request information at the Kent board. I, like you, feel sure Isaac was my great-great grandfather, but to avoid embarrassment if it turns out he's not, I'd first like to make absolutely certain he is, if I can.