This image was taken on 11 March 2016, just after Nancy Reagan's funeral. As bizarre as it may seem to some people, there is a significant amount of affection present in this moment.
George W. Bush's head is tilted toward Hillary Clinton's and her head - particularly her eye/forehead eye is touching 43's cheek/shoulder.
President's Bush is displaying a sincere smile. His forehead is relaxed, his eyelids are partially closed, there are the highly-characteristic concave-up furrows in each of his lower eyelids, Bush's cheeks are vectored primarily upward and only his upper teeth are visible. His smile is absolutely sincere.
Secretary Clinton is laughing - and her laughter is also very sincere. Note that her eyes are closed - a signal of high sincerity both during a smile and laughter. There is also a particular signal in this image which is extremely under appreciated when it comes to interpreting body language - Hillary's jaw retraction. Retraction of the jaw during laughter is a very reliable signal of sincerity. And although she may have a very slight natural overbite, Hillary's dynamic action of the mandible tells us her laughter is true.
See also:
Nonverbal Communication Analysis No. 3495: Donald Trump swarmed by security on stage in Ohio
Nonverbal Communication Analysis No. 3185: Julia Roberts Recalls Her First Interview with David Letterman - a Body Language Indicator of Sincere Laughter
Nonverbal Communication Analysis No. 3394: People react to being called beautiful - Body Language of a Sincere Smile
Negotiation Body Language Secret No. 353: Brad Pitt's Smiling Eyes - Sincere and Insincere Smiles
Nonverbal Communication Analysis No. 3463: Marco Rubio, Robotic Behavior and Insincerity
Nonverbal Communication Analysis No. 3308: Hillary Clinton's Apology - Certainly Late, Yet Was It Sincere?
Nonverbal Communication Analysis No. 2459: Was Eliot Spitzer Sincere? Apology, Sincerity and Body Language
Nonverbal Communication Analysis No. 3371: John Kasich at the Republican Debate
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