Owlbear Cub

Bonded Companion. The owlbear cub obeys It's companions commands. In combat, it acts immediately after your turn and only takes the Dodge action unless you use a bonus action to command it to take another action. If it's companion is incapacitated, it can act however it wishes to protect Them.

Keen Smell. The owlbear cub has advantage on Wisdom (Perception) checks that rely on smell.

Magic Bond. If the cub drops to 0 hit points, it disappears and reappears 8 hours later, fully healed.

Scaling.

This owlbear cub is magically bonded to its ranger companion and grows stronger as the ranger does:
Armor Class: The cub’s AC equals 10 + the ranger’s proficiency bonus.
Hit Points: The cub’s hit points equal 5 × the ranger’s level + the ranger’s proficiency bonus.
Saving Throws: The cub adds the ranger’s proficiency bonus to all saving throws.
Attacks: The cub uses the ranger’s spell attack modifier for its attack rolls.
Beak: 1d8 + the ranger’s proficiency bonus piercing damage.
Claw: 1d6 + the ranger’s proficiency bonus slashing damage.

Beak. Melee Weapon Attack: your spell attack modifier to hit, reach 5 ft., one target. Hit: 1d8 + PB piercing damage.

Claw. Melee Weapon Attack: your spell attack modifier to hit, reach 5 ft., one target. Hit: 1d6 + PB slashing damage.