Um ... . 10 years old, you can have normal sex education ~ Tell her that this is a sign that dad loves mom, and you can tell her how she came first ~ I remember there is a children's version of "100,000 Why", which describes the fertilization process in a cartoon way, which is very suitable for children. And there are many sex education documentaries suitable for children abroad ~ I can show them to your daughter next time ~ I can explain them vividly to her next time. But at the same time, you should also tell her why she can't have sex now, and you can start instilling some moral problems ~ ~ Anyway, don't avoid such problems.