Never seen this before. Two pumpkins apparently generated from same stalk at my residence. I did not directly place either.
There must be a hidden stalk some where. Once a stalk grows a pumpkin, its code gets changed and it isn't possible for the stalk to grow a second pumpkin.
I don't know how that could be. I planted four stalks a long time ago and no more. There are two additional stalks just outside the picture which have single pumpkins on them. Edited: Here's a shot from another angle. I just harvested one of the pumpkins. At 19415 if you want to see for yourself.
You know, plants need a water block within 4 blocks of them, and a light source near enough to them to light them at night for them to survive.
Not melons and pumpkins, once the seed is planted you the land will never turn back to dirt unless broken. my thought on this is two pumpkins generated in the two of the four possible spawn pads there at the same time, the same way a spider and skeleton can spawn at same time to get a spider jockey. The stem just choose that one pumpkin out of the two to attach too.
Because to me it seems weird to take screenshots of the chat when you could just copy the chat log to your screenshots folder.