I stumbled across this exquisite Walt Whitman poem and immediately fell in love. It could be the epigraph for the novel.  (Read the full text at the link.)

We two boys together clinging,
One the other never leaving,
Up and down the roads going — North and South excursions making,
Power enjoying — elbows stretching — fingers clutching,
Arm’d and fearless — eating, drinking, sleeping, loving.
No law less than ourselves owning. . .