for(i = 0; i < 2; ++i){
  pid_t ret = fork();

  if(ret < 0){
    printf("Fork Failed!\n");
    return 1;
  } else if(ret == 0) { //Children process
    pid_t children_ret = fork();

    if(children_ret < 0){
      printf("Fork Failed!\n");
      return 1;
    } else if(children_ret == 0) { //Grandchildren process
     printf("\n [ID =%d] My parent is [%d]\n", getpid(), getppid());
      exit(0);
    }

     printf("\n [ID =%d] My parent is [%d]\n", getpid(), getppid());
    wait(NULL);
    exit(0);
  }
}
 printf("\n [ID = %d] I am the root parent \n", getpid());
wait(NULL);
exit(0);