Why bite the hand that feeds you?

You'll notice a theme in the cats that are in my photos,

I won't tell you what it is, but you'll figure it out.

This  cat is a tom, another one that loved his mom, and one day about 2 1/2 years ago, he left.

3 days later, we look out, and think we see him

but on closer inspection, find it is a longer haired cat, and has a white flea color on.

She wasn't too friendly, nipping my heels when she could.

A short time later, she presented us with these.

Yes, that is PINK under her front paw.

Now for today's story.

She's never wanted held, and always tries to get down, whenever you do pick her up.

Well, Monday afternoon, we were unloading logs from the trailer.  I went over to sit on the larger log, to rest, while hubby used the tractor to lift the logs off.

Here came Mamma Kitty,

 (we've never named her, really, as she just showed up, and we figured she would eventually move on, but she hasn't.)

Anyway, she rubs against me, and finally jumps into my lap.

I pet her a little, she gets down.

Then, she jumps up again, lays down like she wants petted.

So I comply, and all seems to be going well.

 Suddenly she grabs my finger with her mouth, bites me, and jumps down.

This isn't the first time she's done something like this, she used to bite me as I was walking.

But it is the first time in several months, that she has tried this stunt.

OK, have you figured out the 

theme yet?