I found this for you at ff.net. I haven't read it so I don't know if it's friendship or slash, but here: This Side of Paternal (http://www.fanfiction.net/s/5879264/1/This_Side_of_Paternal) by ImagineTheMist
I know a number of kid!fics, but they're mostly with a kid who is not long-lost. So I will be horribly gauche and mention that I've written a fic where Wilson has a long-lost daughter: Lost and Found (http://deelaundry.livejournal.com/74006.html)
I looked for this fic but couldn't find it! I was in the process of searching through Topaz Eyes' rec list and was in the J's just last night. It was, in fact, this fic I was searching for when I found the other fics I recc'd.
no subject
Date: 2010-04-13 11:10 am (UTC)no subject
Date: 2010-04-14 01:40 pm (UTC)no subject
Date: 2010-04-14 02:38 pm (UTC)I've not read this one either, but the author says there will be mild slash.
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Date: 2010-04-14 03:12 pm (UTC)Attack of the Fifty Foot Mary Sues (http://www.fanfiction.net/s/3326900/1/Attack_of_the_Fifty_Foot_Mary_Sues) by BethTX.
no subject
Date: 2010-04-16 02:02 am (UTC)no subject
Date: 2010-04-16 01:11 pm (UTC)Seconding this rec!