How do you break awkward silence?

Answer 1

You can always ask them how their day was or bring up memories that might be shared between the both of you or even say a joke. If you really have nothing to say then just say see you later.

"Amen."

"Do you think pets have sexual dreams about their owners?"

"How about them Lakers?"

"Are we having a moment of silence?"

Answer 2

Try not to talk about sensitive topics, but say "So, Whats up?" and he'll tell you and ask it back and then you tell him and then he comments on what you said and so on...