1)Shayne Terry's Duet... A widowered(??) Clark Kent and his son meet Lois Lane..

2)Also Bakasi's stories.. (I don't remember the name exactly, but it's a series of 3 or 4 stories..), plus I think the child isn't his biological..

3)Sunkist's Above Alt Else... (again the child isn't exactly his biological child.. it's complicated smile )

4) StopQuitDont's Chip Off the Old Clark (this might not exactly satisfy your requirements since he does have a son before Lois but he only comes to know of him after he's involved with Lois)

5) Some of Philip Mogul's "Dr. Clark Kent" stories have him married to someone else and have children before he's united with Lois...

Hope this helps,
wave

If she had to move heaven and Earth, perhaps come back to haunt Perry and explain the story after they'd killed her, she would do it.

Waking a Miracle by Aria