The duo made history in 2016 as the first sisters to walk the now-defunct Victoria's Secret Fashion Show.
But their personal lives have suffered in recent months, with mother-of-one Gigi involved in a high-profile and nasty split with former One Direction singer Zayn Malik.
The former couple – who share 1-year-old daughter Khai, made headlines in October after it was reported Malik had "struck" Gigi's mother, reality star Yolanda Hadid.
He was charged with four counts of harassment – of which he pleaded no contest. In documents obtained by TMZ, Malik was allegedly at the home he shared with Gigi in Pennsylvania on September 29 before an argument with Yolanda broke out.
He allegedly "called Yolanda a f***ing Dutch s**t", and commanded her to "stay away from [my] f***ing daughter".
Malik then allegedly "shoved [Yolanda] into a dresser causing mental anguish and physical pain", though the singer denied any sort of physical contact.
Meanwhile Bella has recently opened up about her "excruciating" mental health struggles over the years.
The model shared a confronting post with fans in November, posting countless selfies showing her in tears.
"Social media is not real. For anyone struggling, please remember that," she wrote at the time.
"Self help and mental illness/chemical imbalance is not linear and it is almost like a flowing rollercoaster of obstacles … it has its ups and downs, and side to sides. But I want you to know, there is always light at the end of the tunnel, and the rollercoaster always comes to a complete stop at some point.
"It took me a long time to get that in my mind, but I've had enough breakdowns and burnouts to know this: If you work hard enough on yourself, spending time alone to understand your traumas, triggers, joys, and routine, you will always be able to understand or learn more about your own pain and how to handle it."
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633 or text 234 (available 24/7)
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (12pm to 11pm)
• Depression helpline: 0800 111 757 or text 4202 (available 24/7)
• Anxiety helpline: 0800 269 4389 (0800 ANXIETY) (available 24/7)
• Rainbow Youth: (09) 376 4155
If it is an emergency and you feel like you or someone else is at risk, call 111.