There’s also a Radio Edit which I think takes out the swearing.
While not a podcast, I thoroughly recommend getting Stephen Fry’s retelling of the Greek myths and legends on Audiobook - “Mythos”, “Heroes” and “Troy”
To add to Mike Duncan’s Revolutions, he also did one about The History of Rome. Again, very detailed so might not suit a 9-year-old, although I read large chunks of Gibbon’s ‘Decline and Fall of the Roman Empire’ when I was not much older so may we underestimate kids sometimes.
Revisionist History is a good listen (very left leaning) but not ancient history in the slightest.
Hidden Brain is quite good about behavioural science. Crowd Science from BBC Worldwide can be quite interesting.