British actress Millie Bobby Brown took to social media to announce she's engaged to actor Jacob Bongiovi, the son of American singer-songwriter Jon Bon Jovi. The 19-year-old actress shared a picture with her 20-year-old fiancé on Instagram, sporting her engagement ring. "I've loved you three summers now, honey, I want 'em (them) all," the 'Stranger Things' actress captioned their picture.