diff --git a/src/main/java/oving4/Person.java b/src/main/java/oving4/Person.java
new file mode 100644
index 0000000..4975b20
--- /dev/null
+++ b/src/main/java/oving4/Person.java
@@ -0,0 +1,89 @@
+package oving4;
+
+import java.util.ArrayList;
+
+public class Person {
+	private String name;
+	private char gender;
+	private Person mother;
+	private Person father;
+	private ArrayList<Person> children;
+
+	Person() {
+	}
+
+	String getName() {
+		return name;
+	}
+
+	char getGender() {
+		return gender;
+	}
+
+	Person getMother() {
+		return mother;
+	}
+
+	Person getFather() {
+		return father;
+	}
+
+	int getChildCount() {
+		return children.size();
+	}
+
+	Person getChild(int n) {
+		if (n < 0 || n >= children.size()) {
+			throw new IllegalArgumentException("invalid index");
+		}
+		return children.get(n);
+	}
+
+	void addChild(Person p) {
+		if (isMale()) {
+			p.father = this;
+		} else {
+			p.mother = this;
+		}
+		children.add(p);
+	}
+
+	void removeChild(Person p) {
+	    for (int i = 0; i < children.size(); i++) {
+		if (p.name == children.get(i).name) {
+		    children.remove(i);
+		    return;
+		}
+	    }
+	    if (p.isMale() && this.father == p) {
+		this.father = null;
+		return;
+	    }
+	    if (p.isFemale() && this.mother == p) {
+		this.mother = null;
+		return;
+	    }
+	}
+
+	void setMother(Person p) {
+		mother = p;
+	}
+
+	void setFather(Person p) {
+		father = p;
+	}
+
+	boolean isMale() {
+		if (gender == 'M') {
+			return true;
+		}
+		if (gender == 'F') {
+			return false;
+		}
+		throw new IllegalArgumentException("Illegal gender");
+	}
+
+	boolean isFemale() {
+		return !isMale();
+	}
+}
diff --git a/src/main/java/oving4/testing/CoffeeCupTest.java b/src/main/java/oving4/testing/CoffeeCupTest.java
new file mode 100644
index 0000000..08e6f24
--- /dev/null
+++ b/src/main/java/oving4/testing/CoffeeCupTest.java
@@ -0,0 +1,37 @@
+package oving4.testing;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+public class CoffeeCupTest {
+
+	private CoffeeCup coffee;
+
+	@BeforeEach
+	public void setUp() {
+	    coffee = new CoffeeCup();
+	}
+
+	@Test
+	@DisplayName("Constructor")
+	public void testConstructor() {
+		assertEquals(0, coffee.getCapacity());
+		assertEquals(0, coffee.getCurrentVolume());
+		coffee.increaseCupSize(10);
+		assertEquals(10, coffee.getCapacity());
+		coffee.fillCoffee(10);
+		assertEquals(10, coffee.getCurrentVolume());
+		coffee.drinkCoffee(10);
+		assertEquals(0, coffee.getCurrentVolume());
+	}
+
+	@Test
+	@DisplayName("volume cannot be null")
+	public void testAddChildException() {
+	}
+
+}