WATCH: Biden's whisper goes viral

Vice President Joe BidenJoe BidenTrump endorses challenger in Michigan AG race On The Money: Democrats get to the hard part Health Care — GOP attorneys general warn of legal battle over Biden's vaccine mandate MORE caused a stir on Tuesday during Secretary of Defense Ash Carter's swearing in ceremony, when he called over the new Pentagon chief's wife and whispered something in her ear. 

It's unknown what Biden said to Stephanie Carter, but his whispered message made the two laugh. 

Biden's move went viral on social media, with GIFs and Vines flooding Twitter to highlight the unexpected exchange. 

Carter was unaware Biden had said something to make his wife laugh, with the two standing behind him as he thanked both President Obama and the vice president for their trust. 

Biden got similar attention in January, when he whispered to the daughter of Sen. Chris Coons (D-Del.) during his Senatorial swearing in ceremony and then gave her a kiss on the head. 

Coons defended Biden, and said he was just being friendly and that his daughter "didn't think he was creepy."

Watch the video above for Biden's latest attention-getting whisper.