Ōzaru 大 猿 - Great Ape - is an ability that allows the Saiyans to turn into a giant ape with their tail if they are exposed to the light of the full Moon multiplying their power. Your child may not be able to do it, but when he cries loudly, no one would doubt it.
The ability to transform into Ozaru only affects the race of the Saiyans or Saiyans and their hybrids with humans. But if you are a fan of Dragon Ball this you know better than well.
What you may not know that the transformation is possible (in theory) thanks to the Bruits waves product of the reflection of a sun on a moon. When these waves come into contact with his eyes, he is excited by the glands in charge of initiating the transformation, which are exclusively in his tails. This explains why they can only transform if their tail is in perfect condition.
Some Space Warriors like Vegeta or Tullece know a technique called Power Ball. They have the ability to create a cluster of energy capable of emitting Bruit waves. This was used in combat to quickly conquer planets, turning all surrounding Saiyans into beasts.