Madison Beer's friend, Jack Phoenix, tragically passed away over the weekend. The 15-year-old guy was struck by a hit-and-run driver, and the "Unbreakable" singer is absolutely distraught. (The authorities are still looking for the suspect, who was being followed by the police when the car crash occurred.)

Jack's family and friends, including Madison, were initially worried about him after he went missing. After news reached about his passing, the pop star posted a photo of her friend on Instagram, along with the caption, "have fun in heaven & try not to cause too much trouble up there?."

She also wrote a powerful message on Twitter about cherishing your moments with loved ones, and powering through dark moments.

This is so heartbreaking. Our thoughts are with Jack's family and friends.

What do you think about Madison's message? Send your condolences and kind words to Jack's loved ones in the comments.