Family issues

Monday, my sister got her money stolen (400 or 300) and my whole family is blaming me and my younger sister. I know I didn’t do it but everyone thinks I did it. No one admitting they want to do a lie detector test.. and they think it was me for sure because my expression when I said it, I was shocked they would even come up with that idea...but I want your guys opinion if takin a lie detector test is too much?

P.s~ my sister said she can make the money quick like in a week