A year later , on June 14 , 1987 , their surviving children visited Jerusalem .
A year later , on June 14 , 1987 , their surviving children planted a tree in the Garden of the Righteous at Yad Vashem .
A year later , on June 14 , 1987 , their surviving children visited Jerusalem and planted a tree in the Garden of the Righteous at Yad Vashem .