It turns out that last year, President and Michelle Obama had a light-hearted "feud" with Prince Harry over the Invictus Games (an international Paralympic event), which Harry started after seeing a similar event in Colorado. He sort of challenged the First Lady who with her husband sent an "in your face" video in reply. And this was Prince Harry's response. (His response includes Michelle Obama's video, which is why I haven't included it.)
This all came up because the 2017 Invictus Games are set to start soon, and the question has arisen if Melania Trump will renew the faux-feud and joking. The general consensus has been...er, no.
Here's Prince Harry's reply. Read his note first before clicking on the video to start it.