Inner Child is an unlockable passive item in The Binding of Isaac, added in the Repentance DLC.

+1 Extra Life.

Upon death, Isaac respawns in the current room with half a red heart (or half soul heart if he doesn't have any red heart containers), and receives:
+0.2 speed.
-50% size.
-73% hitbox size.

Respawning as the inner child emits a blood explosion that deals 35 damage to nearby enemies.

After unlocking, the item is guaranteed to spawn in the hidden closet in the Home floor once the tainted version of the current character has been unlocked.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this item for the previous Repentance version, check this page instead.

Defeat Ultra Greed as Jacob and Esau.

Inner Child can be found in the following item pools:

Below is the Internal Item Description as shown in-game.
Note that some stat changes are not displayed here. Please see the main description for the full effects.

Inner Child

• Grants 1 extra life that revives Isaac as a tiny version with a smaller hitbox and increased speed
• Deals 35 damage to enemies in close range when this extra life is triggered
• Abyss: x1 locust 1x Isaac's damage

• Check out the item description on the external Isaac Wiki.