Why was sucheng Chan's father astounded when he saw his daughter after the war?

Sucheng Chan's father was astounded when he saw his daughter after the war because she had transformed significantly both physically and emotionally during her time away. The traumatic experiences of war had changed her appearance and demeanor, making her seem older and more mature than he remembered. Additionally, the separation and the hardships endured had created a deep emotional distance, highlighting the impact of the war on their family and personal identities.