Bella Hadid thinks it is "weird" to be nice.
The 18-year-old beauty and her 20-year-old sister Gigi think it is vital to work hard and always try and make friends in order to get ahead in their modelling careers, but know that often seems strange to people in the fashion industry.
Gigi said: "What I've been doing a lot every day is I have three goals: be kind, work hard and make a friend.
"When I do those little things on set every day, those are the things that then lead to creating relationships and building opportunities. Because you don't know who those people are gonna go have dinner with and talk to that night."
Bella added: "No matter if they're working next to you, below you, or above you, be kind and generous to everyone you meet. Yeah, it's bizarre because it's weird for people to be nice these days."
The stunning sisters also insisted they would never let a guy come between them, but admitted they don't have the same "type" anyway.
Asked if they had ever fought over a guy, Bella - who is rumoured to be dating singer The Weeknd - told V magazine: "No, never. We would never touch the same person."
And Gigi - who has been romantically linked with Joe Jonas since splitting from Cody Simpson - said: "We don't have the same type."