The Rosemary's Baby star is an outspoken campaigner for refugee causes, particularly those affecting children in war-torn areas, and is a Goodwill Ambassador for UNICEF.
Farrow recently visited a camp in north-eastern Kenya, where refugees are flocking in a bid to find food, and she's horrified at the severity of the crisis.
She says, ""Something huge is happening, and it's terrible. So many of the kids haven't made it, have died along the way. This is an acute emergency.
""The good news is that they are being processed and there will be nourishment for the severely malnourished children. Most of them, I hope, will be saved.
""We're having hard times around the world, I'm aware of that. But they're not as hard as for the people here. I mean, most of us can count on surviving the night. UNICEF needs your help to save lives, the lives of children in the Horn of Africa, who depend on you and me right now.""