Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Hennekam syndrome ?
    ### Response:
    Hennekam syndrome is a rare condition that affects the lymphatic system. Signs and symptoms of the condition are generally noticeable at birth and vary significantly from person to person, even within the same family. Affected people generally experience lymphangiectasia (lymphatic vessels that are abnormally expanded), lymphedema, and distinctive facial features (i.
    