Hi Adam - I have come to believe the “twin” squash is due to an occurrence during pollination. It’s not a bad thing, just something that happens during pollination that causes this. Kind of similar to twins occurring during human pregnancy.

I just pulled 2 (would have been 4) of these weird conjoined squash out of my garden just now and searched the web to see what I could learn about it. I can’t say why it happened, but it doesn’t look like they were just near each other and started to grow together – it looks like they started growing that way…

I have 2 itty bitty squash that are siamese like this and they each have their own flower but share the stem. Most curious