on the superman returns movie where lois and her son where on luthors ship and the boy pushed the piano at the guy. that had to be clarks son i mean it wasnt gladiators son of course who elses son could it have been right .
In the story "Superman: For Earth" Superman breaks the news to Lois that they might not be able to have kids in the first place, and that he should have told her before their engagement. Lois agreed, and they both decided to not have any kids. Lois and Clark got inspiration off of Lois's Aunt, and decided that they can to help a child out any way that they could, whether it be a foster child, or anything along those lines.
I don think the kid starts to develop powers until later on in age... probably not til around 3-5 years old. im just guessing tho. probably the most logical explanation..
Jor-El did choose Earth for him because humans are close to their own DNA - but close is relative.
Put aside Lois for a moment - could Superman reproduce with Wonder Woman? She can 'handle' him physically...
Or would he be forced to become a sperm donor to Power Girl, in the name of continuing the Kryptonian race? (Being a cousin from another dimension - is that far enough removed?)
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"I'm not smart so much as I am not dumb." - Harlan Ellison
in almost every elseworlds story that he and diana have been together (including kingdom come for instance) superman has been able to knock her up. it might be her godlyhood that does it, though, rather than him being adaptable...