Best solution… give them a short nice answer … If they start questioning your choices then ignore their question and change the topic or stop talking or interacting with them. If they still bother you then cut them off. That’s what I’ve been doing recently. I’ve lost my patience and tolerance for such people. It’s none if their business. I’m childfree and live in other country than my home country. This has made it worse. Started seeing true colours of people now, and how they try to push their opinions and choices on me.