Is it obligatory for a wife to dismiss thoughts that cast doubt on her husband's death, and when does her lawful waiting period (iddah) end? And is there any blame upon her if she observes the iddah for two or three days longer than required as a precaution?

She must disregard the whispers (waswas) and pay no attention to them, for a person's death is an undeniable matter. The waiting period (iddah) for widowhood is four months and ten days for a non-pregnant woman, and it ends with childbirth for a pregnant woman, as Allah Almighty says: "And for those who are pregnant, their term is until they deliver their burdens." The waiting period is calculated by lunar months and begins from the day of death.