@LadyMacbeth who told kausalya is not respected. She is a much respected woman of Ramayan. A pious woman with endearing quality of accommodating everything, commitment to her duties, she walked as per the rules of raghukul taking personal pain. Sumitra is admired because of her selfless dharma. Kausalya was expected to do a lot of things as the crown queen and she met those expectations.
Sumitra no one expected anything from her. Vanvass was never for Lakshman. But with the blessing she gives to Lakshman that one sentence takes Sumitra above Kausalya. Because she exceeds expectations.
" From today treat Ram as Dasrath, Sita as myself and let jungle be your Ayodhya." is the blessing this mother gives to her son. And with freewill and pleasantness she allows Lakshman to accompany Ram.