Is It Illegal for a Minor to Stay the Night with an Adult

My question involves criminal law for the state of: Indiana

Is it illegal for an underage minor(15) to stay with an adult(18) if we are not having sex / sleeping in same room and are under supervision.

We have been together two years but my grandmother wants to know the laws. We are not doing anything illegal her parents know and don't care about her staying the night. Just want to know if there is any law that prevents us from staying in the same house together.

As long as the minor has permission to be at the house and there is no sexual contact, nor is there any attempt to engage the minor in sexual conduct or expose the minor to prohibit material it is not illegal.

Grandma doesn't own a couch? And what does "under supervision" mean? Grandma's going to share the room with the two of you?

Seriously, if grandma's better judgment is to keep the child out of your bedroom, she should go with her gut.