How do I answer this question from an Ex Nosy Co-worker?

My ex coworker who I worked with for a few years was always very nosy. I haven’t worked with her in 5 months, but becasue I am pregnant she keeps emailing me all the time with questions about my pregnancy and very private ones like, who is your OBGYN and what time are you scheduled to have your c-section and what is your birthing class schedule? She even tried to get me to go to dinner with her becasue she wanted to see me pregnant when I had sent her pics already! I told her I was too busy to plan dinner and the she called me from a private number AT WORK to chat!Then the last straw was this question I got form her yesterday…

Hi there Mom to be!

If I were to drop off a gift at your home, where would be a good place to leave it if no one is at home??

To me this feels as though she is pretty much inviting herself over to my home which I am so uncomfortable with. I don’t even know how she knows where I live, although she does have my address from eavesdropping on my conversations. I almost want to tell her to mail it, but I don’t know how to respond to this in a tactful way without giving her the okay to just drop by. I don’t like anyone to come to my home unannounced! I feel like if I say just leave it in the mailbox, that gives her the okay to just come by unannounced…HELP!