Introducing Sarath, Anila said, "He is the son of the daughter of the father of my uncle". How is Sarath related to Anila?

Let's break down the statement made by Anila step-by-step from back to front:
1. "my uncle" $\to$ Anila's uncle (paternal or maternal, let's assume paternal uncle i.e., father's brother for simplicity).
2. "father of my uncle" $\to$ Paternal grandfather of Anila.
3. "daughter of the father of my uncle" $\to$ Daughter of Anila's grandfather, which means Anila's father's sister (paternal aunt / Bua) or maternal aunt.
4. "son of the daughter..." $\to$ Son of Anila's aunt.

The son of one's aunt is one's cousin. Therefore, Sarath is Anila's cousin.