Ah, mes, you're absolutely right. Girls that young can be (and often are) completely aware of how they resonate in an adult man.
This weekend I was at a friend's house, a single mom with two daughters. I spent most of the time sitting on the couch with the 7 month old on my lap and the 2,5 year old trying to get my attention in other ways, lol. The mom said 'the baby could sense I was okay because she remained so quiet and at ease'. It's that old 'pedar' thing, I guess.
When girls get older though they still know you're 'okay' but also become aware of their own sexual feelings. And they either use you for that (like when a 8yo was sitting on my thigh and rubbed herself against me) or they match it with what they sense from you (like when they 'tease' you and cuddle or hold your hand like you described).

And its sooo sexy! No amount of intercourse can compete with it and that is something many people don't seem to understand: that for me as an MAA just cuddling or holding hands or playing hard-to-get with a 9yo is more sexy than fullblown sex (that even goes for 'sexy' with adult women, I might add). Its part of that spiritual kind of attraction we have toward girls that may not exclude physical sex but is certainly not exclusively about that.

love

Smeagol