According to media reports, his younger sister collapsed in her London apartment on Wednesday (March 13), and died of an apparent heart attack.
Félicité had a large following of her own on Instagram, where she occasionally shared photos of herself with Louis and their other siblings.
Tomlinson's mother, Johannah Deakin, died from leukemia in 2016. She was 43.
See some of the messages of condolence being sent to Tomlinson below.
Prayers to Louis Tomlinson. I can't imagine how hard it is right now. Love to you brother I'm so sorry and my prayers are with you.— charlie puth (@charlieputh) March 15, 2019
My condolences and prayers go out to @Louis_Tomlinson and his family at this time 🙁❤️— Brendan Murray (@brendan_m96) March 15, 2019
Such incredibly sad news today. You're not on your own in this @Louis_Tomlinson So many people are pulling for you and your family right now x— James Corden (@JKCorden) March 15, 2019