Caught red handed?

"Why did you cover his mouth when he was talking about your brother." Soham asked as they entered their suit. He controlled himself in elevator too but now when there is no one, he needs to know the reason for her reaction. What Ishaan knows but not him?

"I wanted to do it." Serene could have used a lie and coquettish way to get out of the situation but today he irked her a lot by his restrictions and his teasing. 

Soham looked at her with an interrogation gaze. He knows very well that Ishaan knows about her brother Henry but how? Did they meet somewhere else? But what matters to him is what Serene is hiding from him which is known by Ishaan but not him. 

With little coldness Soham asked again. "Serene, why did you touch him? What are you hiding?" Soham asked directly.