I'm with Kodiak, but would speak to the kid first. Not sure there's a way to inoffensively get the kid to acknowledge the adult's paternity/maternity (let's not forget the many women who snatch kids, though IIRC, they usually snatch baby-babies).
But then, the world has experienced a lot of trouble because too many people tried to be inoffensive. "Don't worry dear. We'll just wear this yellow star, not cause any trouble, and they'll leave us alone."
Yeah, right. All the way to the ovens.
Who remembers that little diddy which compared Bernie Goetz with Kitty Genovese?
Cheapo the concerned
Who called 911 last week because the screaming, cussing and thumping could be heard from across the street. From behind closed doors and windows.