M.E.
I feel I must respond with a comment. Last October a burglar entered our house through our second story bath room window (smaller than yours) and stole every piece of jewelery that I owned and more. We left the window open for ventilation and it was not alarmed. The rest of the house was alarmed but the window was so small and high that we didn't think it was an issue. The alarm went off when the thief left but the damage was done. We never got a single thing back. I will never leave a bathroom window open again.