When the head is sick the whole body is sick.
More Dutch Proverbs:
Wake not a sleeping dog.Dutch
A horse may stumble, though he has four feet.
Dutch
When the wine is in the man, the wit is in the can.
Dutch
When it is God's will to plague a man, a mouse can bite him to death.
Dutch
He that will not be counselled cannot be helped.
Dutch
When gnats swarm in January, the peasant becomes a beggar.
Dutch