My five-year-old just asked me- Mummy , can two girls marry each other? How am I supposed to respond to this question?

I like this simple clarification "My kids have known about gay relationships pretty much since they've known about straight ones. People fall in love, some people fall in love with people who are of the same sex, sometimes they don't. Simple as that. What they have a really hard time understanding is why some people are so mean to other people just because they want to be in love."