Kids!Clex (just a little older...)
These fics start when they meet as kids, but follow through them until they are adults and start having a relationship
Two Halves
Summary: Two halves make a whole, even when they don't remember. A 'what if' Lex found Clark before the Kents did story.
This one has lots of emotional h/c, it’s a very sad story, with Ryan, but has a happy end for clex.
Dolimir is one of my fav. standalone story writers.
Someone To Watch Over Me
Summary: What if the government had stepped in and collected people affected by the meteors when Clark was still a toddler?
Both by dolimir dolimir_k
Destiny's Couple
by Bleudiablo
Summary: Lex returns to Smallville a three months after the meteor shower and meets a young, silent Clark. Their friendship is a thing of Destiny no matter when it started.
Family Portrait
by Perryvic and Tzi
Summary: The Kent family is a mosiac that keeps shifting and moving itself in the oddest ways. Additions, subtractions, temporary divisions, but most of all, remember one thing. Watch out, or the silverfish will get you.
Maybe Baby
by Jas Masson
Summary: Lex has a problem.
This is only Lex reverting to childhood. Somehow cute, and somehow sad.
A Change in Habits
Summary: A story of wee!Clark and younger!Lex meeting in an alternate timeline
Awareness
Summary: Sequel to A Change in Habits. Pamela had kidnapped Lex instead of leaving, creating a different chain of events.
Both by Mobiusklein mobiusklein
Consanguinity
by paperbkryter paperbkryter
Summary: Clark seeks to remember something from his childhood, and believes Lex may be the key.
Idyllic Life
by perryvic, Zaganthi (Caffiends)
Summary: Part 1 - Jonathan was giving Martha 'Help' looks that screamed confusion. It was one thing to have to raise a three year old; another to bring a child who was almost ten into the family. Part 2 and so on Lex is in college and Clark, of course is much older than three.
World Enough and Time
by Arysteia
Summary: Part 2 of her series Lex and Clark: The New Adventures of Superman. For once Clark has a good excuse for being late. It involves time travelers. Lex couldn't possibly take that badly. Could he?
Kid Stuff
by LaceyMcbain laceymcbain
Summary: At the end of the JLU episode “Kid Stuff”, they don’t immediately turn back into adults...
Grasping At Straws
by askaniblue
Summary: Clark tells Bruce a story about a childhood mistake that nearly cost him his life.