Alison Arngrim: (about Melissa Gilbert) Everyone thinks that she is my mortal enemy. I swear, to this day, people are still asking me, "So, do you really hate her? Do you still see her?" What people find almost impossible to believe is that she's practically like my baby sister. If you're going to play people like that on a show, where you're smacking each other in the head all the time, you're going to have to become friends, and Melissa and I became friends the first day. We both wanted a friend on set, someone to be like a sister to us, and we hit it off right away. To this day, it's as if we're related. We grew up together. We share so many memories, and so many things in our minds, that are the same.