All right then, you've got two treefrogs in your area- the gray treefrog complex (Hyla chrysoscelis and/or H. versicolor, I'm not sure which is there) and the green treefrog (H. cinerea). I can't tell which it is based on the photo, but the fact that it's breeding in a pool makes me think it's a gray. Greens seem to prefer large permanent wetlands, while grays will breed just about anywhere there's a few inches of water.

He'll be easy to ID once he transforms: Gray treefrog metamorphs have a dark lateral streak and a pale spot below the eye, like this:

Green treefrogs look just like the adults, with a white lateral stripe (often missing in frogs in your area) and sometimes with yellow flecks on the back:

Good luck raising your little guy!