An unknown destiny: book one. Riverkit's clan

Riverkit was born from lionflame, of thunderclan, and Mya, a lost kittypet, when her and her brother, darkkit, get lost, they return to find that their mother had died of greencough. They become lost again and darkkit becomes ill, riverkit drags him all the way and finds thunderclan, only to see that their father has passed away too.

What will she do?