I thought my horse wandered away when I was loading in but I was not sure so I got a second horse and I leashed it (so it could not wander away) and then got on it and exited and then logged back in and it was gone.
This is related to the resolved bug on Console Edition MCCE-3913
Here is also a subreddit that is tracking the bugÂ
https://www.reddit.com/r/Minecraft/comments/bhwi1s/my_horse_disappeared/
Thank you for your report!
We're actually already tracking this issue at MCPE-51837, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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