I see, well that means that each of the twins is fertilized by a sperm cell.
In fraternal twins, each twin is fertilized by its own sperm cell
My cousin just gave birth to twin boys Neat, so she has two offspring from the same pregnancy now. Yeah, she had a daughter first but it's still an unexpected surprise. They're fraternal but I don't know what that means.
In fraternal twins, each twin is fertilized by its own sperm cell.