Gerbie

This story is too funny for those of us reading it. After you catch the frog, sterilize the toilet or I would anyway. I would then have DH or someone else to climb on the roof, and use some screen wire like for a screen on doors or windows or get some hail screen larger blocks in the wire, cover the open pipe and use some strapping metal strips with holes in it, to wrap around the excess screening and then get a clamp like they use on hoses for car radiators and screw it down tight to prevent future invasions. you could get these at your local Lowes or Home Depot or any hardware store. If a frog could get in other varmints could as well, perhaps even a snake, I have heard of that - snakes can climb trees, and would eat frogs. Your vent will still get the air it needs, but will prevent anything from getting down the pipe and prevent a huge plumbing bill in the future. My DH had to do this to our vent to prevent base balls from getting in it when neighbors wild grandchildren would toss bb and other things on our roof, being the "angels" they are not.