Canto 2 -
Ayodhyā-kāṇḍa
Chapter 61: Kausalyā Condemns Daśaratha in Extreme Distress
Text 2.61.15

एवं कनीयसा भ्रात्रा भुक्तं राज्यं विशां पते।
भ्राता ज्येष्ठो वरिष्ठश्च किमर्थं नावमंस्यते॥

evaṁ kanīyasā bhrātrā bhuktaṁ rājyaṁ viśāṁ pate
bhrātā jyeṣṭho variṣṭhaś ca kim arthaṁ nāvamaṁsyate

evam = in the same manner; kanīyasā = by His younger; bhrātrā = brother; bhuktam = enjoyed; rājyam = the kingdom; viśām = of the citizens; pate = O lord; bhrātā = brother; jyeṣṭhaḥ = the elder; variṣṭhaḥ = wiser; ca = and; kim artham na avamaṁsyate = why would not reject.

O lord of the citizens, in the same manner, why would the elder and wiser brother not reject the kingdom enjoyed by His younger brother?

She connects her point with her example here. Variṣṭhaḥ indicates that [Rāma] is superior [to Bharata] by His auspicious attributes. Why would He not reject the kingdom? He will certainly reject it. [This was Kausalyā’s contention.]