My question involves emancipation laws for the State of: Missouri

My 15 year old sister lives in Missouri. Our mother has been charged with a felony for child abuse in addition to being an alcoholic. I realize that my sister cannot finacially support herself, but I am willing to financially support her. She does not wish to live with my family and I because her friends are in Missouri. Stupid I know, but she's 15. I am her legal guardian, but I live in another state. Can I emancipate her? If not, how can she become emancipated?