I saw part of this film many years ago and this is all I can remember…
Two characters discuss a young woman, “a girl who never grew up”, or similar wording. The implication is that the woman has the mind of a child. We then see the woman in question, sitting in a pushchair or wheelchair, being pushed along a path in a park by a nurse. They are going from left to right and away from the camera, with a hedge or some kind of shrubs to their left.
The camera pans away to show another part of the park. Then it pans back and we see that the nurse and woman and pushchair have all suddenly vanished. They didn’t have time to walk out of shot if they were carrying on down the path. The music becomes dramatic to emphasise the disappearance.
Later a search is carried out and the wheelchair is found in some bushes, along with a golliwog doll (like one of these).
The film is in colour (must be 50s or 60s judging by the type of colour and the costumes) and most if not all of the characters have American accents.
Any thoughts welcome.