you need to tell her that something intresting will happen when she/he goes to sleep.
I fu_k my little sister when i go to sleep last night.. She is outrageous...
my question is how can i convince my brother in law to get my sister to mental health
Ask her - she can only say yes or no.
It's not adviseable - incetuous activity can cause serious psychological damage to you and your sister.
First of all: why would you want to sleep in the basement? Do you hate yourself or something!?
prove/convince him that you're not a horndog bent on stripping his poor sister of her innocence.
Tell her that she could be infected
You can't. It's not really your business.
Is it uncomfortable to sleep with your sister? That should answer your question.
yes.
It's best to convince her! Or even try to bribe her.
you don't go to sleep