Looking like a lot of her classmates – giddy and irreverent, wearing a silly necklace of Blow-Pop lollipops strung together with curly gift ribbon – Bristol Palin stepped toward the stage in Wasilla Sports Complex Thursday night to receive her high school diploma, more a worried mom than a jubilant teen.
"Where's my baby?" Bristol mouthed, searching the two front rows where her family sat until she finally spotted son Tripp near the backstage door, where Bristol's Aunt Heather was feeding the infant a bottle. With a wave to the little one she alternately calls "Handsome" and "My Guy," Bristol crossed the stage – and crossed "graduate high school" off her to-do list.
"I knew it would be hard work, but I knew I was going to do it," Bristol, 19, tells PEOPLE.