Hair length

Okay so I have a wee bit of a problem. I've been trying to grow my hair out for YEARS now (honestly maybe my whole life XD) and my hair just doesn't grow. It might have something to do with my brother cutting it while we were playing hairdresser when I was like 5, but I doubt it. I love my hair! It's soft and curly… I just wish it was longer. It's like halfway to my shoulders. Do any of you have hair-growing tricks that I could try? Thanks for your help!