On Monday, the Fox News host tweeted a link to an article about Mr Biden kissing his 19-year-old granddaughter Finnegan during an event in Iowa with the headline: “Biden awkwardly kisses granddaughter at campaign stop.”
Hannity also included the hashtag #QuidProJoe, before following up with another tweet in which he asked his followers to take a poll about whether the display of affection was “Creepy or not creepy?”
While the tweet prompted some to side with Hannity, others took the opportunity to point out that Donald Trump also kisses his relatives on the lips, including his adult daughters.
In response to Hannity’s tweet, one person shared a photo of the president leaning in to kiss daughter Ivanka on the lips during an appearance in Manchester, New Hampshire.
Another tweeted: “Do you mean creepy like this?” alongside a photo of a teenage Ivanka sitting on her father’s lap and kissing his cheek.
During an appearance on The View in 2006, Mr Trump was asked how he would feel if Ivanka decided to model for Playboy. He responded: “It would be really disappointing – not really – but it would depend on what’s inside the magazine.
“I don’t think Ivanka would do that, although she does have a very nice figure. I’ve said if Ivanka weren’t my daughter, perhaps I’d be dating her. Isn’t that terrible? How terrible? Is that terrible?”
The former vice-president isn’t the only notable figure to face criticism for kissing a younger family member on the lips.
Even among experts, there is no correct answer about whether kissing on the lips is acceptable behaviour or not.
While child and educational psychologist Dr Charlotte Reznick first raised the question in 2010, when she asked: “If you start kissing your kids on the lips, when do you stop?” others in the field have disagreed.
In 2015, Dr Fiona Martin from the Sydney Child Psychology Centre said that anything that promotes “emotional connectivity,” such as a kiss, is a good thing.
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