S1·E586 Nanhi Gavah

On very rare occasions do you find a witness to a murder. CID this time has a witness to a murder, who was close enough to see everything and brave enough to not run away. A little girl who witnesses a brutal murder but the trauma was too much for her to handle, she has gone mute since the murder. The officers struggle to get anything out of her. How does CID tackle this sensitive situation?