Would a guy lie about kids?

So I recently started asking my boyfriend if he wanted kids and marriage and he seemed a bit freaked out. We've been together almost two years and never brought stuff up like this. He said it was weird I was asking but a little longer into the conversation he said he wants two kids, maybe two red head girls or a redhead girl and a brown haired boy (he has a thing for red hair, obviously). So that made me feel a little better. And I asked if he wanted me to have his babies and he said yes to that also. Now, I'm just wondering if he was saying those things to appease me..has anyone had a guy do that to them? I'm only wondering because he seemed really freaked, like caught off guard. I had to tell him I thought it was perfectly natural to fantasize even if we don't end up together in the long run...then he said those things about kids. I'm worried he said that to not upset me! He's older than me and at an age where, if he were a woman, would probably really want to start a family, lol. I know men think differently than us so do you think a guy would lie about something so serious?