President Trump to Mueller: "Does it ever stop?"; Trump slams Mueller testifying, accuses Dems of "Do-Over"; President Trump's lawyer responds to Mueller testifying; Image of dad and toddler drowned in Rio Grande illustrates humanitarian crisis at the U.S. Border; Trump on Photo of drowned migrants: "I hate it," it could stop if the democrats change the laws; Warren leads in polls among her debate night stage mates; De Blasio, Ryan, Castro, Booker, Warren, O'Rourke, Klobuchar, Gabbard, Inslee, Delaney face off tonight; Warren, Klobuchar visit migrant detention center ahead of debate; What to watch for in tonight's first democratic debate; Hours away: 2020 Dems face off in crucial debate; Sen Scott weighs in on Dems' debate and diversity in GOP; Sen Scott discusses border crisis and heartbreaking pic; Sen Scott reacts to sexual assault allegations against Trump; Sources: new flaw found in Boeing 737 Max; Trump on upcoming talk with Putin: "What I say to him is none of your business"; Trump takes parting shots before meeting with world leaders at G-20 summit; Trump seems to take another dig at late Senator McCain; Barr busts out the bagpipes via Knit