I don't know how I missed this movie! It's called "Vanishing Twin" and was made in Korea in 2002.
'Vanishing Twin' is the medical term for a twin that died in the mother's womb. But it also has the psychological meaning of a basic fear-the other half to disappear. Following the traces of her sister's death, 'Yu-jin' finds herself yearning for her sister, whose charisma differs from Yu-jin's comfortable life. As she does this, Yu-jin begins fighting with herself. There might be, inside ourselves, a different self already dreaming a different dream. This different truth, which we cannot remember, is the motif for the film, "Vanishing Twin."
Yu-jin is a successful museum curator who leads a satisfying life with her husband and beautiful daughter, Min-ji. One day, she hears that her twin sister will be coming to town from the United States. She feels both excitement and trepidation at the same time. Seung-jin, her twin sister, is quite different from Yu-jin. She possesses a special charisma that Yu-jin and many other people find attractive. Yu-jin even admires her. As her arrival date approaches, Yu-jin cannot help but feel nervous. Her feelings are justified when her brother-in-law arrives alone bearing horrible news of her sister's suicide. Unlike Yu-jin who is devastated, her husband and friends are unusually calm.
And when her brother-in-law tries to seduce her, she feels a strange physical familiarity to him. Suffering from the aftermath of her sister's death, Yu-jin meets a stranger on the web who calls himself an art lover. He alludes to the suspicious circumstances surrounding Seung-jin's death and Yu-jin finds herself discovering her sister's past. Art lover awakens physical and psychological memories within Yu-jin that she never knew she possessed. Is she the vanishing twin? The answer to the puzzle lies within her.
We have books about vanished twins: here is one:
The wiki page
Vanishing twin seems to be a reasonable page, and you do see these words duplicated throughout the Internet:
But when you read the discussion pages on Wikipedia you see the confusion: (There was a page about womb twin survivors once, placed there by me, and complete with references etc, but was soon removed and some of the detail merged with the vanishing twin page)
Read the discussion and notice the confusion.
Please will some one else put up an edit on the discussion page and maybe mention some of my books and articles, ( see bibliography here, just copy and paste) so it doesn't always sound like me plugging my own web site?