Watching your first mother with your siblings..

I just had a thought over the past couple of days... Is it weird to watch your first mother interacting with your siblings or 1/2 siblings? I'm in kind of a weird situation in some ways. My girls are 5 and 7, my son will be 25 and he and his fiancee will be visiting us for nearly a month this summer. So far, our FTF situations have been over a couple of days and with others from our families involved. This will be a chance where we'll really get to know each other (I hope), and I started thinking, he's going to get to see me in 'mom' action, you know? And I know that when I've looked at pictures of him growing up, I feel pangs of those times missed...since I'll never get those... I guess I'm wondering if adoptees feel the same sorts of things from the other side, is it possible that he'll see me being mom and think 'huh, that's how my life could have been...' (not that it would have exactly but you know what I mean). Thanks for any input!