I've seen a fair few Drama Specials, and this one is easily the worst.
The conceit is basically that a mysterious boy intrudes into the heroine's life - he waits until she's attracted to him to completely humiliate her by revealing he's her estranged little brother!
Sorry to anyone who expected this to be a romcom, judging by the promos and the cast and the first half of the special! I left this special disgusted and I wouldn't recommend it to anyone. If you wanted a story about romance and was sorely disappointed by this, watch Bride in Sneakers or If We Were a Season or Buzzcut Love. If you want a GOOD story about family, watch I Introduce My Father or Summer Dream or Rural Outcasts. You deserve better than this trash!