Whenever the old man thinks of the son he lost young, he is overcome with grief.
Tips
history
From the Analects: 君子坦荡荡,小人长戚戚, 'the gentleman is calm and open, the petty man is forever anxious'. Li Qingzhao's ci 《声声慢》 opens with seven doubled words ending in 凄凄惨惨戚戚.
usage
心有戚戚, from Mencius, means to feel something stir in your heart: 'I feel exactly the same'. Here the word is sympathy, not worry.