[OB] The identity of the sibling

[desi_sparta]

So now that we know that even the oathgates have sprens, I think I have a theory on the third Bondsmith spren. It's the spren of Urithiru.

The reason the tower of Urithiru dues not function properly is because it's actually the physical manifestation of the sibling. The stormfather, while discussing the sibling with Dalinar says that you disturb them enough at it is. I suppose people poking and prodding the entire tower on a daily basis could be construed as disturbance. Additionally, the tower can only become fully functional only when someone has bonded the spren, providing it sentience. Otherwise, the tower (read: physical body) regresses back to its basic functioning like a storm or a windspren. And only someone who can understand the tower intimately will be able to bond its spren. 

An additional point of thought is the refusal by sprens of Thylenah's oathgates to grant entry to Shallan from cognitive realm. They told her that they have been forbidden to do so by someone. Stands to reason that such an order can only be given by a spren that ranks higher then them. Say a spren of the building that has all ten oathgates. 

What do you guys think?

[Bort he/him]

I was under the impression that the refusal came because in his final days, Honor/Tanavast decided the Oathgates couldn't be used to transport people between the Realms.

I do agree with you about Urithiru though. There is a more thorough thread around here, about Navani bonding the Sibling, that looks at just this idea.

[recneps he/him]

Yeah, I do believe the Oathgates were told not to by Tanavast. The Sibling being Urithiru is corroborated by the gem-records - I believe it was them at least - which talked about  the Sibling being upset making things weird.