Summary
All naturally spawning mobs that can despawn should despawn. Naturally spawned baby sheep and baby cows despawn correctly when player moves more than 54 blocks away from them. Baby pigs do not despawn when the player moves 54 blocks away.
How to reproduce
Create a world in latest beta.
Wait for baby pig to spawn.
Move 54 blocks away from it.
Attached low quality gif due to limitations.
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We're actually already tracking this issue at MCPE-76373, so I will resolve and link this ticket as a duplicate.
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