Lyric discussion by Xxmintt 

Cover art for Smile lyrics by Uncle Kracker

I agree with kejade; I also think it's about his daughters. Especially the line that says, "I see the best of me inside your eyes." Also, kids make their parents happy like this- like, the "fall out of bed" line could be the feeling of being woken up at sunrise by kids. All parents know how that feels... Plus, the metaphors and similes are simple and child-like, such as "Cooler than the flip-side of my pillow." Which makes a lot of sense, if it was written for his kids.

However, it could also be interpreted as a simple love song.