u/Due_Ad6576

Just recently within the past 2 weeks had my sister in law moved in with me and my wife. She’s young, beautiful and very girly.
Any suggestions to see if she would be interested in possibly doing something with me? She’s young and talks about sexual things but not about her sexual life though. How do I go about this and see if she would be interested in something without possibly letting my wife know I want something to happen?