C, Some statements in fork() not executing

I think I understand how fork() works, yet only some of my statements in the body execute. For example, in each conversion block, all the printf() will execute yet png_count, gif_count, and bmp_count never increment and remain 0 (as an be seen in the printf() output for child(x);

/* Create Processes */
    printf("\n+++++++++++CREATING PROCESSES+++++++++++\n");
    int i, pid;
    png_count = 0;
    gif_count = 0;
    bmp_count = 0;

for(i = 0; i < convert_count; i++) {
        pid = fork();
        if(pid < 0) {
            printf("Error: fork failed");
            exit(1);
        } 
        else if (pid == 0) {
            /* Child execution */ 

            /* PNG conversion */
            if ((getpid() % 2) == 0) {
                image_in_path = getInPath(input_dir, png_images[png_count]);
                image_out_path = getOutPath(output_dir, png_images[png_count]);
                printf("image_in_path: %s\n", image_in_path);
                printf("Child (%d): %d\n", png_count+1, getpid());
                png_count++;
                printf("Converting: %s\n", image_in_path);
                execlp("convert", "convert", image_in_path, "-resize", "200x200", image_out_path, NULL);
                exit(1);
            }
            /* GIF conversion */
            else if ((getpid() % 3) == 0) {
                image_in_path = getInPath(input_dir, gif_images[gif_count]);
                image_out_path = getOutPath(output_dir, gif_images[gif_count]);
                printf("image_in_path: %s\n", image_in_path);
                printf("Child (%d): %d\n", gif_count+1, getpid());
                gif_count++;
                printf("Converting: %s\n", image_in_path);
                execlp("convert", "convert", image_in_path, "-resize", "200x200", image_out_path, NULL);
                exit(1);
            }
            /* BMP conversion */
            else {
                image_in_path = getInPath(input_dir, bmp_images[bmp_count]);
                image_out_path = getOutPath(output_dir, bmp_images[bmp_count]);
                printf("image_in_path: %s\n", image_in_path);
                printf("Child (%d): %d\n", bmp_count+1, getpid());
                bmp_count++;
                printf("Converting: %s\n", image_in_path);
                execlp("convert", "convert", image_in_path, "-resize", "200x200", image_out_path, NULL);
                exit(1);
            }
        } 
        else {
            /* Parent Execution */
            wait(NULL);
        }
    }

output:

+++++++++++CREATING PROCESSES+++++++++++
image_in_path: idir/panda.bmp
Child (1): 5389
Converting: idir/panda.bmp
image_in_path: idir/panda.bmp
Child (1): 5393
Converting: idir/panda.bmp
image_in_path: idir/penguin.gif
Child (1): 5397
Converting: idir/penguin.gif
image_in_path: idir/bmp.png
Child (1): 5402
Converting: idir/bmp.png
image_in_path: idir/bmp.png
Child (1): 5408
Converting: idir/bmp.png
image_in_path: idir/panda.bmp
Child (1): 5413
Converting: idir/panda.bmp
image_in_path: idir/panda.bmp
Child (1): 5417
Converting: idir/panda.bmp
image_in_path: idir/penguin.gif
Child (1): 5421
Converting: idir/penguin.gif
image_in_path: idir/panda.bmp
Child (1): 5425
Converting: idir/panda.bmp
image_in_path: idir/panda.bmp
Child (1): 5429
Converting: idir/panda.bmp

Thanks in advance for the help! I've spent way too many hours trying to figure this out with no luck.