Closing Nonduplex Unnamed Pipes in C

I have 8 children, and am trying to use 8 pairs of nonduplex unnamed pipes to communicate with them. Thus, I have 2 pipes for each child and 16 pipes in total (one for childRead_ParentWrite and the other for parentRead_ChildWrite).

Anyway, my main question is when to close the pipes. I was taught to initially close the sides that are not being used by the process, and then when the process is finished with its side of the pipe, to close it off. However, I am brand new to the subject and am having some trouble. Here is my code:

// The 16 pipes
int fd_childReads_ParentWrites[8][2];   // Parent closes 0, Child closes 1
int fd_parentReads_ChildWrites[8][2];   // Child closes 0, Parent closes 1

// The 16 buffers
char buf_ChildReads_ParentWrites[8][80];
char buf_ParentReads_ChildWrites[8][80];

// CREATE THE PIPES

// FORK THE CHILDREN


// Manage processes
if (pid == 0)   // CHILD
{
     printf("I am the child: %d\n", getpid());
     // Close the appropriate pipe ends
     close(fd_childReads_ParentWrites[playerNumber][1]);
     close(fd_parentReads_ChildWrites[playerNumber][0]);


    // CHILD DOES STUFF WITH PIPES 


    // When finished, close the working child pipe ends
     close(fd_childReads_ParentWrites[playerNumber][0]);
     close(fd_parentReads_ChildWrites[playerNumber][1]);
}
else   // PARENT
{
    printf("I am the parent: %d\n", getpid()); // NOT BEING PRINTED

    // Close the appropriate pipe ends
    for (i = 0; i < NUM_PLAYERS; i++)
    {
        close(fd_childReads_ParentWrites[i][0]);
        close(fd_parentReads_ChildWrites[i][1]);
    }


    // PARENT DOES STUFF WITH PIPES


    // Finally, close the working parent pipe ends
    for (i = 0; NUM_PLAYERS < 8; i++)
    {
        close(fd_childReads_ParentWrites[i][1]);
        close(fd_parentReads_ChildWrites[i][0]);
    }
    // Wait for the children
    for (playerNumber = 0; playerNumber < NUM_PLAYERS; playerNumber++)
    {
        wait(NULL);
    }
}

I must be doing something wrong. The program prints out the correct number of children, but the parent's printf() line is never printed. When I take out all of the close() functions it prints, but even taking out solely the children's close()'s doesn't print he parent line.

If someone could explain to me the correct way to close nonduplex unnamed pipes in a situation like this, that would be awesome.