I got married when I was 26 and had a small candid picture from the wedding on my desk until recently. I have my kids' most recent school picture facing towards me. Wedding picture is gone because my husband cheated on me so I don't like to look at the wedding picture (working on it - the marriage, not the picture

).
Of my colleagues, everyone over 35 or so has family pictures. Seems like 30-35 is hit or miss, and under 30 it's rare. Not sure if it's a generational thing or just because the older you get, the more kids you have, etc.