I am sharing this purely because it amuses me, not because it's helpful.
My female ex-partner and I told DD about how she was made (intra-uterine insemination, aka turkey baster) when she was quite small. She gathered the basics of this well, and educated her reception class about how two women go about having a baby.
A couple of years later I tried for a baby with a very repressed gay male friend of mine, of whom DD was fond. DD chose this time (she was 7) to ask me rather more about how babies were made. She watched some videos of blastocyst formation with me and we talked about IVF, and at some point she asked how mums and dads like her friends mums and dads had babies. So I explained that the sperm is made in the testicles, and little tubes carry it down to the penis, and a man can then use the penis to put it inside the woman's vagina, and it swims up into the uterus, and if there is an egg in the fallopian tube coming down from the ovary, the two might come together and make an embryo.
I was very proud of myself for keeping a reasonably straight face and nodding gravely when she explained yes, she knows about testicles, she's seen them on boys before.
Unbeknownst to me, she then decided to sue my gay male friend for extra info. He turned up rather white and drawn-looking to hand DD back to me as usual. We left his, and I asked DD if he'd seemed ok. 'Oh yes,' she said, 'I just asked him a bit more about testicles and so on, since he'd know better than you'.