Why does my mom need my paystubs and stuff?

Hello! My mother and I (m18) live in a rental and she sent an offer in for a house and it got accepted. She asked for my ssn, tax returns and paystubs and bank statements. Why does she need these? Tried asking in realstate but they took it down!!!

Edit: Thank you all for the answers, I’ve read and I will ask her again what she really needs these documents for.