Implement project Professional_L1.2 (Collections)

@kostiantyn-kuzin please review
is it ok?
public static void ShowHeirs(this Collection<Person> persons, string parentName)
        {
            Person parent = persons.FindByName(parentName);
            if (parent != null)
            {
                Console.WriteLine("{0} heirs:", parentName);
                foreach (var item in parent.Heirs)
                {
                    Console.WriteLine(item.Name);
                } 
            }            
        }