This is that John Kelly. He was Secretary of Homeland Security.
This is also John Kelly, but not that John Kelly. He's a Washington Post columnist who regularly tweets from his @JohnKelly handle.
@JohnKelly often tweets about squirrels.
"You’re much more likely to see a squirrel than a shark," Kelly told BuzzFeed News.
"Every April, I do a week’s worth of columns about squirrels."