How do I properly create a function within a function prototype? 
What I have is this:

```
    <body>
    <p id="demo"></p><script>
function person(first, last, age, eye) {
    this.firstName = first;
    this.lastName = last;
    this.age = age;
    this.eyeColor = eye;
}
person.prototype.name = function() {
    return {
        myFunc: function() {
          this.firstName + " " + this.lastName;
       }
      }
};

var myFather = new person("John", "Doe", 50, "blue");

document.getElementById("demo").innerHTML =
"My father is " + myFather.name().myFunc; 
</script>

</body>

```

When I run this it returns "My father is function () { this.firstName + " " + this.lastName; }" , but I was expecting John Doe.