“Help us to stay alive….” Those were the last few words of 15-year-old son Mahmoud and seven-year-old daughter Sham's message on social media, days before they were killed along with their mother and eight relatives by Israeli airstrikes in Gaza. They were the immediate family of the Al Jazeera bureau chief Wael Al-Dahdouh, a 53-year-old journalist with years of experience in conflict reportage.