This dad was no fan of the dab. House Speaker Paul Ryan was sworn in the 115th Congress Tuesday and then took part in an hours-long photo op with members and their families. Cal Marshall, the 17-year-old son of newly elected Rep. Roger Marshall, a Republican from Kansas, decided to make it more interesting—for him, and for scores of viewers, namely those younger than the politicians—by dabbing. The adults were not impressed. "Just so you know @SpeakerRyan: He's grounded," Roger tweeted. It is unclear if he was being serious. "Do you want to put your hand down?" Ryan said. "You gonna sneeze? That...