I wouldn't worry about the kids. For reasons unbeknownst to me, this picture seems to be a curiousity for adults.
Chelsea Clinton kissing like most people do. Let's have a hissy fit.
Most of us don't do it in public, in front of the cameras of the tabloid press. (Does the expression "get a room" come to mind?)
She ought to know that, as a semi-public figure, the daughter of the formerly most powerful man in the world (gag, ack, ptui!), her behavior is going to be observed and commented upon by many, especially when she maintains a high-profile, globe-trotting, fashion show-attending, movie premiere-frequenting, dining at all the "in" bars and restaurants lifestyle. Therefore, she would be advised to demonstrate a little decorum. Instead, her behavior is low-class and tacky, even for a 22-year-old.