Crash when bringing tamed dogs in a nether portal

Me and my friends were playing in my survival realm, and we were going on an adventure in the nether. I brought my dog with me and all of a sudden, we got disconnected. We joined back and it looked like the realm didn't save. We had to restart what we did for the past hour.

 

I really hope this does never happen again. I would hate to restart my realm.

Please fix this soon