UPDATE: The Queen just got in on the action. Her response to the Obamas' challenge is quite simply perfect.
Remember when the Obamas went to England and hung out with the Royals earlier this month?
They may all be smiling there, but apparently Prince Harry issued a challenge before the Obamas left, inviting them to "bring it" at the Invictus Games, a sporting competition for wounded, injured, and sick military personnel that he started. The next event starts May 8 in Orlando. Consider the challenge accepted.
Harry quickly fired back.
So, this is officially our favorite Twitter fight of all time.
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