"The fathers and the mothers are smiling."

[Girishkorgaonkar]

Is Kepi muñi līrisi issi right as well?

[Xenon-]

In High Valyrian the Present tense is expressed by one word, there is no reason to put the verb 'to be' there; it doesn't work as in English. So, no. (You also forgot the macron in muñī)