Sam always stands at the crosswalk impatiently, eyes fixed on the street lights opposite them for when Dean will let him go. Dean keeps a firm grip on his little brother's hand, rolling his eyes as cars speed by.
This is his job, he thinks, and there's a smile there, too, despite himself, making sure Sammy can't get hurt.
The light changes. The cars roll to grudging stops. Dean waits another few seconds to make sure no one runs the light.
And Sam, as soon as he can, charges forward so fast that Dean stumbles after him, hand in hand.