American Girl dolls are more popular than ever. All my five-year-old niece wanted for Christmas last year was an American Girl Doll and my sister couldn't refuse.

If you're the parent of a child with an American Girl doll, them you know how expensive the dolls are and how many accessories and extras that go along with each collection.

One of the main reasons the American Girl franchise is so successful is because they've got dolls from different decades, with different histories and back stories. They've also got the option for you to build a doll that looks just like your child. From ethnicity to hairstyle, every girl can customize their doll to look just like them.

10-year-old Melissa Shang loves American Girl dolls, but she can't get her doll to look just like her – because she has Muscular Dystrophy and American Girl doesn't feature any disabled characters. So, Melissa and her older sister took to the internet, made an adorable video and started a petition to change the face of American Girl.

Melissa's petition has over 130,000 signatures and this is what it says:

"When I was seven, like most of my classmates, I fell in love with American Girl dolls – historical and modern girls with stories about overcoming obstacles. I’ve read all of the books, seen all of the movies, and even visited the American Girl Place in New York City. For the past three years, I’ve asked for an American Girl doll for Christmas.

However, none of the American Girl "Girls of the Year" are like me. None of them have a disability.

Being a disabled girl is hard. Muscular Dystrophy prevents me from activities like running and ice-skating, and all the stuff that other girls take for granted. For once, I don’t want to be invisible or a side character that the main American Girl has to help: I want other girls to know what it’s like to be me, through a disabled American Girl’s story."

Right now, you can buy a wheelchair as an accessory for any doll, but apparently none of the American Girl dolls has a story or book about being disabled. American Girl hasn't responded to the petition yet.

Why shouldn't there be an American Girl doll representing girls with disabilities? I can't think of a single reason and so I've signed Melissa's petition. If you'd like, you can sign it too right here.