After Cal's conversation with Dax, he told Reed what he suspected, and why Dax was asking all the questions...
CAL- "I think Dax may be trying to understand his sexuality."
REED- "Seriously, that is what you got out of the conversation?"
CAL- "Why else would he be asking if I knew I was gay before I met you, and about you having Lee with Michaela."
REED- "It could just be curiosity, but then again you may be right. I mean it's highly likely that one of our children may be gay."
CAL- "Yeah, I know. I am just glad he feels comfortable talking to us about it. I am sure he will figure it all out."
REED- "Yes, How about we go to bed and call it a day?"
Meanwhile, Dax has snuck out of the house....
DAX- "So, Alysia you still going to meet me, I am on my way there now."