They are certainly something in the Solanaceae, which Moonflower is, if by 'Moonflower' you mean Datura stramonium. The top two plants are slightly distorted, whether by growing conditions or bugs, but imo they could easlily be the same species as the third plant. Being a short lived perennial in the right conditions the top two shoots could be returning from roots while the third is clearly a seedling. Being in the centre of the pot would support that idea.

BTW there is a specific forum for plant identification here on GW, frequented by precicesely those people who "kinda enjoy the challenge of seeing a random plant and trying to figure out what it is".Name That Plant! - GardenWeb (houzz.com)

Thanks for the info! I discounted Moonflower (yes, datura) because of the bulbous shaped leaf that looks totally different from the ones I grew from seed. The leaves are also darker. But I'm gonna let it go and see what it turns in to :-)

I had no idea that other forum existed, thanks for that, too! LOL I said this in another post, but Houzz is almost cursed with having TOO many subforums. It also didn't suggest that subforum when I posted the thread, so that would've helped.

Slight tangent here, but... now that the sprout has gotten bigger, my plant app agrees that it's a Moonflower. But it looks a lot different from the seedling that I planted!

So which do you think I should keep, the one that's returning from the roots or the one that I planted a seed? I really only have room for one :-O

Returning perennial leaves often look different from seedlings. From your other posts I got the impression you have lots of space. Why can’t you keep them all?

I guess I technically could. I just keep the datura in a pot so that I can easily move it before it throws a million seeds everywhere, and I only have this one big pot set aside for the Moonflower.

If you think they'll both be equally healthy, I guess I could put one in the ground and just cut it down when it starts developing pods.