I have been able to verify this with three different players. If they have a bird on their shoulder, even if they are not the ones who tamed it, when they stand in a nether portal, it will not teleport them.
Related issues
Comments


Thank you for your report!
We're tracking this issue in MCPE-27950, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
Note that general game play issues should be reported to the MCPE project unless they are known to only happen on a realm, so it is recommended to search in that project first.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – ✍️ Feedback and Suggestions – 📖 Game Wiki
Please cancel this ticket as I was finally able to find another ticket regarding this issue.