请问下如何解释这段 Java 程序第一次输出时 I have $0？

public class Main {

    static class Father {
        private int money = 1;

        public Father() {
            this.money = 2;
            this.showMoney();
        }

        public void showMoney() {
            System.out.println("I am father, I have $" + this.money + ".");
        }
    }

    static class Son extends Father {
        private int money = 3;

        public Son() {
            this.money = 4;
            this.showMoney();
        }

        @Override
        public void showMoney() {
            System.out.println("I am son, I have $" + this.money + ".");
        }
    }

    public static void main(String[] args) {
        final Son son = new Son();
        System.out.println("I am son, I have $" + son.money + ".");
    }
}

输出结果

I am son, I have $0.
I am son, I have $4.
I am son, I have $4.

后面两行我都能理解，但是第一次输出时为什么 money 字段是 0 ？

谢谢