A woman whose husband has died, and whose sister’s husband died one month later: may she visit her sister during the waiting period?

Question:
Honorable Shaykh, may Allah grant you success. A woman’s husband has died, and she is currently in the waiting period. One month later, her sister’s husband died, and her sister is also in the waiting period. The question is: is it permissible for her to visit her sister during the waiting period and go out to her?

Answer:
During the day, there is nothing wrong with it. As for the night, no; at night she must stay in the house. Yes.