FWIW, as someone who found out by surprise that I was a sperm-donor child (and that I have at least one half-sister who was equally surprised by the knowledge of an unexpected half-brother) I find the expressions of the people in the photographs extremely relatable. It's pretty much the exact expression I had on my face when I first found out, which is essentially a combination of "wow this explains a lot of things" + "what the fuck" + a constant background oscillation of "but this changes nothing/everything/nothing/everything/nothing/everything". I'm in my mid-40's, so it's not a generational thing.