Barn cats

We had been catless for a year or two; it wasn't really our choice, because we like to have cats in the barn that will kill the mice and rats, as well as the pesky sparrows that poop on Cliff's tractors.  However, the last few cats who came here to live either decided the barn was their personal litter box or wandered off into the night, never to be seen again.   
I've seen ads on Craigslist, people who had free barn cats that were spayed and neutered.  But when you bring adult cats to a new place, they often leave as quickly as they came, so I remained catless.  I even had a Facebook friend offer me some cats, but I was afraid they would be too tame.  The trouble with cats who have been pets is that they don't stay in the barn; they come to the house and make nuisances of themselves by sneaking through the door every time it opens, or climbing on the window screens and leaving holes for the flies to get through.   
After the neighbors to the west abandoned their house, I started seeing some cats lurking around what used to be my cabin; it appeared to be a mother cat and three kittens.  I started giving them milk every time I milked the cow, and later bought some cheap cat food to supplement the milk.  The mother cat was obviously a pet, but if she came too near the house to suit me, I could hiss and she'd run away.  I refrained from petting her because I didn't want her at the house; but I could tell she would have enjoyed being petted.  
Little by little, the cat family moved to a wing of the barn, so I began feeding them there instead of at the old cabin.  However, there were now only two kittens, one a calico about half the size of the other.   
A couple of days ago the cats disappeared.  When I'd call "Kitty-kitty-kitty", they didn't come running as was their custom.  For thirty-six hours I didn't see any cats, although I faithfully left milk and cat food for them.  
I decided perhaps the little girl whose pets they once were had come and gotten them, although as wild as the kittens were, I couldn't see how she would have loaded them up.  
This morning I went to milk and there the cats were... minus the calico runt.  So now I have two cats, a mother and a daughter.  I'm hoping neither of them disappears.  Perhaps the coyotes I heard yesterday morning ate the runt.  These things happen.

That's the mother in the background at the milk pan.  

It's really hard to get both cats in the picture.  They can be posing prettily, but when I approach, they jump down and head their separate ways.  The kitten is on the pile of boards. 

Mother Cat, begging me to please pet her.  I think I'll call her Lucky, because she reminds me of a good old mouser by that name that I used to have.

Miss Lucky, Jr., posing prettily.   
So, here's hoping neither of these disappear.  I'm getting a little attached to them.  Lucky is behaving so well, I think I'll let my granddaughters pet her next time they visit... but only if they pet her in the close vicinity of the barn.