LAN games

So, i’m trying to play a game with my sister for LAN games. We live together but it says when i play a game and my sister is trying to join me, it says on her screen “friends are not playing.” And when i invite her it says “cannot join world.” Please fix this, i just want to play Minecraft before i leave to go to the pool. Have a great day Mr./M’am.

-Leia