WHIT? >> PIERRE THOMAS, THANK YOU. >>> TONIGHT JUST DAYS AFTER THE SCHOOL SHOOTING AND AMID GROWING CALLS FOR GUN REFORM, THE NRA HAS OPENED ITS ANNUAL CONVENTION IN HOUSTON. MOUNTED POLICE ON PATROL BETWEEN THE CONVENTION CENTER AND THE MASSIVE CROWD OF PROTESTERS WHO GATHERED NEARBY. SEVERAL SPEAKERS AND PERFORMERS CANCELED APPEARANCES IN THE WAKE OF THE SHOOTING, BUT FORMER PRESIDENT TRUMP STILL CHOSE TO ATTEND. ABC'S RACHEL SCOTT IS THERE. >> Reporter: TONIGHT, NEARLY 300 MILES FROM THE SCENE OF THE UVALDE MASSACRE, PROTESTERS DESCENDING ON HOUSTON AS THE NATIONAL RIFLE ASSOCIATION KICKED OFF ITS ANNUAL MEETING. WHY'D YOU DECIDE TO COME OUT? >> BECAUSE MY DAUGHTER IS A TEACHER, AND SHE HAD TO LEARN HOW TO PACK BULLET WOUNDS IN HER CLASSROOM IN ORDER TO TEACH. SHE IS IN A CLASSROOM, AND I FEAR FOR HER LIFE EVERY DAY, EVERY DAY. >> Reporter: INSIDE THE NRA CONVENTION, ATTENDEES SAY GUNS AREN'T THE ISSUE. THERESA WAKEFIELD, A GUN OWNER AND GRANDMOTHER OF 13, SAYS AFTER UVALDE, LAWMAKERS SHOULD RECONSIDER THE LEGAL AGE TO BUY A GUN. >> WHY SHOULD YOU BE ABLE TO BUY WEAPONS AT 18? IT'S HEARTBREAKING, BUT GUNS DON'T KILL PEOPLE, PEOPLE KILL PEOPLE. THE GUNS DIDN'T JUMP ON THE TRUCK, THE GUNS DIDN'T RUN TO THE SCHOOL, THE GUNS DIDN'T DO IT. THAT YOUNG BOY DID. >> Reporter: IN THE HOURS BEFORE THE MEETING BEGAN, SEVERAL HIGH-PROFILE REPUBLICANS BACKING OUT OF APPEARANCES, TEXAS SENATOR JOHN CORNYN AND TEXAS LIEUTENANT GOVERNOR DAN PATRICK. TEXAS GOVERNOR GREG ABBOTT ALSO NOT APPEARING IN PERSON, CHOOSING INSTEAD TO SEND A PRERECORDED VIDEO MESSAGE. >> WE'RE GATHERED TODAY -- >> Reporter: STILL, SENATOR TED CRUZ TAKING THE STAGE AND THEN HEADLINER, FORMER PRESIDENT TRUMP. >> THE EXISTENCE OF EVIL IN OUR WORLD IS NOT A REASON TO DISARM LAW-ABIDING CITIZENS WHO KNOW HOW TO USE THEIR WEAPON AND CAN PROTECT A LOT OF PEOPLE. THE EXISTENCE OF EVIL IS ONE OF THE VERY BEST REASONS TO ARM LAW-ABIDING CITIZENS. [ APPLAUSE ] >> Reporter: AND BACK IN WASHINGTON, THE SENATE DOES PLAN TO HOLD A HEARING ADDRESSING GUN VIOLENCE AND CHILDREN. AS FOR THOSE BIPARTISAN TALKS ON GUN CONTROL LEGISLATION, WELL, CONGRESS IS OUT ON RECESS, BUT THAT GROUP DOES PLAN TO SPEAK BY PHONE AND BY ZOOM. PROTESTERS HERE HOPE THAT THEY DO NOT LOSE THE URGENCY, WHIT.