I read or heard this when Hannah was a baby and I don't remember the source of it, but it really stuck with me:
As a parent, never be the one who ends the hug first.
That's it. Let the child be the one who breaks away from you after a hug.
I have been amazed at what this can do- comfort for the child when I wasn't aware that they were having a tough time, especially in those middle years.
Sometimes I would hug one of my children and they would just keep squeezing me- they needed that emotional comfort- and I had no idea. But I kept hugging- not pulling away- until the child was "done". The change in the child's countenance was amazing- peaceful, relaxed. I didn't even have to know what was troubling them and most of the time they didn't tell me, but whatever it was, they felt better afterwards. The incredible power of human touch!
Now, if the child also receives this advice (never be the one who ends the hug first), you could be in for some REALLY long hugs...