By last year, Cheerios had learned the lesson: Its two-minute “how to dad” ad showed a cool, calm father doing it all, with mom nowhere in sight, and it racked up 1.6 million YouTube views (though it only ran in the U.S. after a trial in Canada). And Nyquil put out an ad showing a dad begging for a sick day from his kid, not his boss, with the tag line “dads don’t take sick days” — it was virtually identical to a similar ad targeting moms.

Why the change in attitude? Advertisers and TV writers are just catching up to demographic trends. Married couples haven’t been in the majority for the past five years, a decline from 78 percent in the 1950s to 48 percent by 2010 (which means the old standard of a mom who ran the home and a dad who didn’t know what to do once he was back from the office no longer makes much sense). In most two-parent families, Pew research shows, both parents are working outside the home at least part-time. And in a growing number of them, dads are the ones taking care of the domestic end: Between 1995 and 2011, the number of stay-at-home-dads in the U.S. nearly tripled from 64,000 to 176,000.

It was about time all this changed.