I don't think phrase

Can "I don't think" be used to say "No" in a less straightforward way?

IE.

CONTEXT: Someone is hosting a party, and two other people are planning on going. The brother got really mad at the person, and has not appeared, and locked himself in his room, even when it was time to leave. He has made no action to leave his room, and is obvious the person is planning on not going.

"Is your brother coming to our house?"

"I don't think so, he has been avoiding me all day. Maybe if you talk to him, you can persuade him."