Conjoined Twin Abby Hensel's Sister Brittany Not Listed As Wedding Witness

Conjoined twin Abby Hensel did not list her sister, Brittany, as one of her witnesses at her wedding ... something we've now confirmed through an official document.

TMZ has obtained Abby and Josh Bowling's marriage certificate, and it provides some interesting information, including the fact that Brittany Hensel -- who partially shares a body with Abby -- is not on the witness list ... although another Hensel sibling is.

Abby put down her other sister, Morgan, as one of her witnesses ... and somebody named Cosmo Naut is listed as the other witness, presumably offered up from Josh's side.

BTW, we're not entirely sure if "Cosmo Naut" is a person or not -- it's obviously a play on the actual word cosmonaut (a Russian astronaut) ... and this could well be a pet.

In any case ... there are a few other deets from the cert, including the fact they got married at the Jerome Event Center in Delano, MN. It was there that Rev. Sid A. Veenstra officiated their nuptials ... which, as we reported, went down in 2021 -- November 13, to be exact.

Also of note ... Abby changed her surname in the marriage, going from Hensel to Bowling.

As we reported ... word of Abby and Josh's marriage raised a lot of eyebrows, and got people asking a lot of questions -- which drew the ire of the twins on social media.

They were clearly annoyed with all the renewed attention they'd been getting -- especially over something that was technically old news ... but which had been kept private 'til now.