While playing locally with my sister (she was on PS4) we noticed that Teire kept disappearing. When we noticed this, we tested it extensively. We opened new worlds on different devices (Windows 10, PS4), noticed the coordinates and the animals, walked a few 100 blocks and then back to the animals, but they weren't there anymore. For the first time we noticed the bug when we fenced in 3 sheep and half an hour later there was no more sheep.