Peter, it turns out, is not the only one in a tree.
There are a number of reasons you like being in tree.
Reason one: it makes you feel tall. You aren't exactly too terribly short, but you spend most of your time with your sister, who is basically a giant compared to you.
Reason two: most of your life is lived on the ground. You have no issue with the ground, but sometimes it's nice to get a different perspective on things, and being in a tree affords that pretty well.
Reason three: trees are very comfortable, and whoever says otherwise is objectively wrong.
So yeah, you're in a tree, and Peter's in a tree, and by your standards that pretty much makes you immediate friends. Different trees - for now, at least - but close enough that you spot him immediately as he makes his way up. He might not see you, and honestly that wouldn't be so strange: you already have a solid collection of lichen and moss and bark growing off you, and the boughs around you have somehow grown denser than they really have any right to be. Honestly, you look more tree than human yourself, all tucked away and coated in nature.
So when you call out to him, well, who could blame Peter if he thinks the trees have begun talking? Though you're certainly distinguishable if he squints, but... yeah. Not saying a lot. "Hullo! D'ya see anythin' interestin' in your tree?"
