What to do in this situation...?

There is an 8yo girl, a friend of the family, very cute, tall, mixed-race, you know the type. I have known her a few years since she was younger (obviously), and now notice her starting to grow up. Who wouldn't.

A year ago or so I was on the sofa with my legs out on the floor, crossed but straight, and she climbed onto them, facing away from me, and began moving her 'self' up and down on my shins. 'All very innocent' I thought, and I moved my legs away to do the right thing. After all I used to do similar things I'm sure when I was younger.

As we've grown closer though, she will greet me with hugs, and now even emails me "I love you and miss you so much!!! xxx" for no apparent reason. She just appreciates me for who I am, although I have done nothing special nor encouraged (or discouraged this).

I have had to stay over on occasion, and she has begged her parents to let her sleep in my room, or camp downstairs with me. But it just seems she could be saying this because she wants to be grown up, not through some physical attraction. I know I didn't find girls attractive until I was about 12, so how could an 8yo girl find me attractive.

When I am at her house visiting the friends, if it is her bed time, she will come down in her PJs and give everyone a goodnight kiss, seemingly intentionally leaving me till last - yet I notice she seems to have given them all a kiss just SO she can come to kiss me. I say this as I happen to know she doesn't always give the family a kiss goodnight, unless I am there and she's in the mood to. Then she comes to me, kisses me on the cheek or lips, then walks away. I say, "goodnight", as if to start the process again and she feigns a 'sigh' and comes back to give me another kiss, and I say "goodnight", and she comes back again. She'd do it forever if I let her.

Then things started to get strange... I was talking to her Dad one time and she just started sucking my arm! We all know what that feels like, but I kept my composure and just ignored it - not even wanting to be seen to react as if I thought anything of it, good or bad.

I don't remember how but this - when her Dad was not around - turned into her sucking the knuckle of my thumb. I became curous as to this, and so I opened my thumb and indeed she took the whole thing in her mouth.

:O

If I tried to take it out, she would scream like a little baby, and I'm sure that on the face of it that is all this is from her point of view - like a comfort blanket.

I explained to her that she shouldn't ever do this in front of anyone else as they'd think it was 'strange'. Dangerous territory?

I was in front of her family recently but with some commotion going on, and her face lit up and she said to me "suck!?" and pulled my index finger into her mouth. Luckily due to the commotion nobody noticed, and I just said, "noo", like a disapproving parent saying no to more sweeties.

So there it is. A cute 8yo girl (below my normal AoA which has a core of 12-15) who wants to suck my finger, sends me love notes, and finds excuses to kiss me.

Yet my dilemna is it all just seems to be explained off as completely non-emotional and non-sexual from her. The sucking is like a comfort blanket, the kisses just like she'd kiss her Mom, and the love notes frivolous childish follies.

For me of course, I see the adult side of it all - but my question is can this girl possibly know what she is doing and how she is flirting with me? Although I NEVER would, in my wildest considerations I have wondered what would happen if she came to stay the night, shared my bed, and wanted to suck my finger again... where it might lead to... But as I said, I NEVER would do this - yet an adult can't help but wonder such things when a female offers to put part of your body in their mouth and complains when you take it out...!

It's the oddest of situations I tell you! :-S