Upon seeing Winnie tuck smiled why was this unusual?

Winnie Tuck's smile was unusual because it contrasted sharply with the somber and serious nature of the situation surrounding the Tuck family. Typically, smiles in tense moments signal happiness or relief, but in this case, it indicated a deeper understanding and acceptance of their unusual circumstances and immortality. The smile reflected a sense of peace with their eternal existence, which was jarring to those who perceived the gravity of their situation.