No. The three children were arrested and taken into a room individually. They were then told that the other children were being tortured, and that they would be as well unless they confessed it was a lie. They did not deny what they had seen. Blessed Jacinta and Marto only lived a few years before they died, but Sr. Lucia died in 2005.
The Fatima appearances are inspiring for many, but it may be good to point out that the Church does not require belief in them.
Scott