Valmiki Ramayana Aranya Kanda Sarga 17 Shloka 24

सदा always, प्रवृद्धनिद्रः in deep sleep, महाबलः very strong, कुम्भकर्णः च Kumbhakarna, धर्मात्मा a righteous one, विभीषणस्तु Vibhisana also, तु but, राक्षसचेष्टितः nature of the demon, न not, रणे in war, प्रख्यातवीर्यौ both very wellknown heroes, खरदूषणौ च Khara and Dusana, भ्रातरौ two brothers.

Kumbhakarna is another brother of mine. He is very strong. He is always in deep sleep. Vibhisna another brother. He is righteous free from any demoniac trait. My other two brothers are Khara and Dusana who are wellknown heroes of war.