[mowhaugh]

Unless you have anyone else locally with a Shetland tup who you would be happy to take the 4 to, for tupping?

Will investigate this. Could easily have some visiting wives to Ken in exchange!

[mowhaugh]

I'm with Anke - I'd really rather a Shetland or similar size tup for a first-timer.  But if not possible, then I'd go with the tup that'll give the lowest birth weight of the options you have available.  I'd worry about her tummy muscles carrying the lambs more than I'd worry about the actual lambing itself - Shetlands are pretty generously sized in the birth canal.

Given the size of Cheviot store lambs, that might even mean the Cheviot would be a contender?  (I've never lambed Cheviots, so don't know what size lambs they have at birth.)

Both the  Kerry Hill and Cheviot lambs are pretty wee at birth - much less size difference between their lambs and a shetlands than you would think from the relative size of the adults. The Kerry lambs probably look bigger, but it is all legs, and they are extremely narrow. So that is probably the best bet if we do have to go for the other breed of tup option.

[princesslayer]

I don't have any practical sheep advice but I know that the emotional needs of a three year old boy should not be underestimated! My boy always responds best to new suggestions by me saying 'I've got a great idea...!' Works every time. Good luck!