What is the waiting period (iddah) for a woman whose husband has died, who are the people she is permitted to meet during this period according to Islamic law, and is it permissible for her to meet her sister's husband?

The 'iddah (waiting period) for a widow has two cases:

- If she is pregnant: Her 'iddah ends upon delivery of her child, based on the Almighty's saying: "And for those who are pregnant, their term is until they deliver their burdens."

- If she is not pregnant: Her 'iddah is four months and ten days, based on the Almighty's saying: "And those of you who die and leave wives behind - they, [the wives], shall wait concerning themselves for four months and ten [days]."

As for those before whom she is permitted to appear, they are only her mahrams (unmarriageable kin). She is not permitted to appear before non-mahrams except with the lawful hijab and without seclusion.