Well, without more context, it's difficult to say exactly. It could be a story where four brothers overcame great odds together. Maybe they grew up in a tough neighborhood and had to rely on each other. They could have been involved in a sport together and achieved great things as a team of brothers. Or perhaps they had a family business that they built from the ground up with their combined efforts.
Since I don't know the details of this 'four brothers true story', it could be a story of four brothers in a war - they might have fought side by side, protected each other and made sacrifices for their family and country. It could also be a story about their journey in the field of art, music or literature, where they supported and inspired each other to create something great. There are so many possibilities.
I'm not sure specifically which 'four brothers true story' you're referring to. It could be about four real brothers who had various adventures, or it might be related to a family drama, business they ran together, or some other aspects of their lives.