How can you determine if kittens are boys or girls and what are the key differences to look for?

To determine if kittens are boys or girls, you can look at their genitalia. Male kittens have a small distance between the anus and the genital opening, while female kittens have a larger distance. Additionally, male kittens have a visible scrotum, while female kittens do not. These are the key differences to look for when determining the gender of kittens.