Mandy's brother's age is four times her age, so his age is 3 * 4 = 12 years old.
Mandy's sister is five years younger than her brother, so her sister's age is 12 - 5 = 7 years old.
The age difference between Mandy and her sister is 3 - 7 = -4 years.
However, we can't have a negative age difference, so we take the absolute value of -4, which is 4.
The age difference between Mandy and her sister is 4 years.
#### 4
The answer is: 4
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
If Mandy is currently 3 years old and her brother's age is four times her age, while her sister is five years younger than her brother, what is the age difference between Mandy and her sister?

### Answer:
