In Words of Radiance, Stick is talking through Pattern making the stick alive with a spren. In Oathbringer Pattern talks about dead things.
"Humans don't care about the dead. You build chairs and doors out of corpses! You eat corpses! You make clothing from the skin of corpses. Corpses are things to you."
Wouldn't that make stick dead? Or if a part of a living breaks off would that make a new spren? Then it would being up the question if 2 or more things are put together would the spren combine into 1 spren? Note I haven't read more then what is in the Stormlight Archive.