Stray cats spawn in/get stuck in soulsand

I have a pretty big netherwart farm right beside my villager village, was getting netherwarts and heard a few cats meowing, searched everywhere for them, finally found 3 different ones stuck IN soulsand blocks. Netherwart farm is a closed building, so they most likely spawned IN the soulsand (entire floor is soulsand). They were unable to move, and weren't taking any suffocation damage.