New to Java

In the example below, it prints out "true" when the Child objects a and b are different. Should I overide equals and hashCode method for every class which extends Person?

public class EqualsTest {
	public static void main(String[] args){
		
		Child a = new Child("Tom",10,1);
		Child b = new Child("Tom",10,2);
		System.out.println(a.equals(b));
		
		
	}
}

class Person{
	private String name;
	private int height;

	private volatile int hashCode = 0; 

	
	public Person(String n, int h){
		this.name = n;
		this.height = h;
	}
	
	@Override
	public boolean equals(Object obj) {
		if(this == obj){
			System.out.println("hello");
			return true;
		}
		if(obj instanceof Person){
			Person a = (Person)obj;
			if(this.name.equals(a.name)){
				return true;
			}else{
				return false;
			}
		}else{
			return false;
		}
	}
	
	@Override
    public int hashCode () { 
        final int multiplier = 23; 
        if (hashCode == 0) { 
            int code = 133; 
            code = multiplier * code + name.hashCode(); 
            code = multiplier * code + new Integer(height).hashCode(); 
            hashCode = code; 
        } 
        return hashCode; 
    } 

}

class Child extends Person{
	
	private int age;
	
	public Child(String n,int h,  int a) {
		super(n,h);
		this.age = a;
	}
}

Thanks