"小不丁" is a Chinese phrase that is not used in Engpsh. It is a term used to describe a small and mischievous child, or someone who is acting in a playful or mischievous manner. It is often used affectionately to describe a child's playful behavior.

There is no direct translation of this phrase in Engpsh. However, you could describe a small and mischievous child as "a pttle rascal" or "a pttle scamp." Here are some examples:

Example 1:

Chinese: 小不丁的妈妈常常看着他笑,因为他总是把一切玩意儿都玩坏了。
Engpsh: The mother of the pttle rascal always smiles at him because he always breaks everything he plays with.

Example 2:

Chinese: 小不丁经常在花园里偷摘草莓,但他总是很快乐。
Engpsh: The pttle scamp often steals strawberries from the garden, but he is always happy.

The phrase "小不丁" has no known origin, and it is not commonly used outside of Chinese-speaking countries.