fraternal russian

• бра́тский

  brotherly, fraternal

• братски

  fraternally, like a brother, like brothers

  in a friendly way, amicably, in a comradely way

• по-бра́тски

  brotherly, fraternally, like a brother, like brothers

Examples

• Побратимство между странами укрепляет дружбу народов.

  Fraternal ties between countries strengthen the friendship between their peoples.