@Michal Thank you, however I may have found the reason for the disappearances. I had a nether portal surrounded by fences with a carpet on it, I thought the villagers couldn't jump on the carpet and would be safe, but I went through the portal and found some of them wandering about... I was wrong apparently. I have since moved it into a building with a door and half slab and so far haven't lost the villagers I spawned to test... I will let you know if anything weird presents itself. Thanks again.
@Michal Thank you, however I may have found the reason for the disappearances. I had a nether portal surrounded by fences with a carpet on it, I thought the villagers couldn't jump on the carpet and would be safe, but I went through the portal and found some of them wandering about... I was wrong apparently. I have since moved it into a building with a door and half slab and so far haven't lost the villagers I spawned to test... I will let you know if anything weird presents itself. Thanks again.