A Baby Nautilus from Minecraft Live! Yippee! Ta-da! Hooray!
The Nautilus Pet - A Forums Suggestion. 
The Brainstorming. 
With the most recent Minecraft: Live, I thought it would be nice to have a Baby Nautilus Pet.
Quick Minecraft Live Overview.
They added the Nautilus, including a Zombie Nautilus (for some reason) that Drowned can ride. The regular Nautilus can be tamed using Puffer fish and can be used as a mount, giving Water Breathing when riden. Along with the water addition, we have a brand new item: Spears! Crafted with two sticks and any type of ingot, you can carry around the Spear. It has two attacks: Jab and Charge, which are very cool additions. The update is called Mounts of Mayhem, and will be released after the Copper Age update.
Obviously, it needs to have variants. Why not have the Zombie Variant, and maybe even the armor? Heck, maybe even a little Trident Drowned could be riding it (probably not, but one cold dream)!
The Model. 
These are all of the variants I have in mind. For some reason, the official Minecraft website didn’t have the leather or diamond armoured Nautilus, but just remember that’ll be there. Obviously, they’ll be the baby version of the Nautilus, but I couldn’t find a Zombie or armoured version of the baby.
Here is some concept art by @Gr33nPuffin !
Such beautiful artwork, right?
Final Thoughts. 
This pet should cost around 880 Minecoins. That’s about it. Thanks for reading!
Contributors.
@ImNotBritish107 - Creator.
@MaybeCreaks - Co-Creator.
@Gr33nPuffin - Model Maker.