DD (who's 2 1/2, we've had chickens from before she was born) "plays" with them when ever we go out. She carries around Silkies and gives them rides in her little toy shopping cart (LOL...that reminds me of someone) and stroller. She has also taken them on the swing or down the slide with her.
The chickens are smart, if they don't like it, they get out.
She's not allowed to hit them, or pull feathers, anything like that to the bird. She knows if they are flapping around to put the bird down, they don't want to be held anymore.
The only really naughty thing she does is will occasionally toss them in the air, which of course she gets in trouble for. It's not so traumatic for the chickens with regular feathers but the poor Silkies.
She has never injured a bird, though and most of my birds are easily handled because of all the attention.
Of course, wash hands a lot and if we are going to be outside a while I keep a little bottle of hand sanitizer in my pocket.