September 27: Booster rollout challenges. Latest from Amtrak crash. Gabby Petito’s funeral and continuing search for Brian Laundrie. TODAY Exclusive — head of Instagram on app’s effect on teenage girls.

<p>Booster rollout is officially underway as many states are now scrambling to get third shots in millions of Americans — this as some ICU’s struggle with surge in hospitalizations. Latest from the Joplin, Missouri train crash. Plus, Gabby Petitio’s funeral held on Sunday as the manhunt for Brian Laundrie is about to stretch into its third week. Also ahead, has Instagram become too toxic for teenage girls? In a TODAY exclusive — Craig Melvin speaks with head of Instagram, Adam Mosseri, on what is being done to create a safer space.</p>