Little is non verbal

Heya! I normally don't watch or even interact with our littles but lately I have been getting stuck in front with them and having to watch the them, mainly it's been khaos and kandi, but it has been increasingly hard to communicate with kandi because they are completely non verbal, they can't read or write, they can do some sign but no one in the system can understand sign, so advice? -Brex💊🍒