Valmiki Ramayana Ayodhya Kanda Sarga 46 Shloka 15
Original Shlokaसभार्यं सम्प्रसुप्तं तं भ्रातरं वीक्ष्य लक्ष्मणः। कथयामास सूताय रामस्य विविधान् गुणान्।।2.46.15।।
1 source checked for this shloka
लक्ष्मणः Lakshmana, सम्प्रसुप्तम् fallen asleep, सभार्यम् along with wife, तं भ्रातरम् that brother, वीक्ष्य having seen, सूताय to the charioteer (Sumantra), रामस्य Rama's, विविधान् various गुणान् virtues, कथयामास narrated.
Having seen that his brother along with his wife had fallen asleep, Lakshmana narrated the many virtues of Rama to Sumantra.