Giuseppe Di Matteo is the most famous example, but they have been killing children even before Riina and the Corleonesi:

Michele Navarra in Corleone in 1948 poisoned the boy Giuseppe Letizia who was hospitalized after having a breakdonwn because of seeing Luciano Leggio killing the political activist Placido Rizzotto. Navarra was a doctor working in that hospital.

Paolino Riccobono from Tommaso Natale was killed by the Cracolici clan in the 60s, bound and shot in the head just because he was a relative of the opposite group.

Both were little more than 10 (maybe 11 or 12).

There are other cases (I don't remember all of them) when children have been intentionally killed by organized crime in Italy, and even more cases when they were killed because of being in company of somebody who was the real target.

Anyway, my main point is that there never was an "old mafia that didn't kill women and children". The old mafia was no better than Riina's gang, even more hypocritical because they pretended to be benefactors and used naive people to lure them on their side.