Valmiki Ramayana Ayodhya Kanda Sarga 8 Shloka 5
Original Shlokaभरतादेव रामस्य राज्यसाधारणाद्भयम्। तद्विचिन्त्य विषण्णाऽस्मि भयं भीताऽद्धि जायते।।2.8.5।।
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रामस्य for Rama, राज्यसाधारणात् having equal claim to rule the kingdom, भरतादेव from Bharata only, भयम् fear, तत् that matter, विचिन्त्य having thought over, विषण्णा अस्मि I am dejected, भीतात् from the person who fears, भयम् fear, जायते हि will be born.
Since Bharata and Rama have equal claim to the kingdom, Bharata is a source of fear for Rama. Having thought over this matter, I am dejected. Danger springs from one who is in fear.