Posting some pics of the latest project.
Kids have been wanting this for a while.
It is perhaps less of a "treehouse" than simply a raised platform amidst the trees. But it is supported by trees at one end.
Framing coming along. Not exactly "to code" but it will be sturdy.
House will be (is) 42 sq ft, with a little porch and a sleeping attic. After the fence, the ground falls off so when up in the house, you are 20 or so feet above the sidewalk.