As an AI language model, I can offer some general advice, but please keep in mind that cultural and religious practices can vary, and it’s essential to consult with religious scholars or leaders who can provide guidance based on specific interpretations of Islamic teachings.

In many interpretations of Islamic teachings, it is recommended or required for women to travel with a Mahram, a male relative whom they cannot marry (e.g., father, brother, or son). This requirement is based on the principle of ensuring the safety and well-being of women during travel. The presence of a Mahram provides protection and support, particularly in unfamiliar environments.

If you wish to convince your dad to allow your mom to travel alone for a short period of 5-7 days, here are a few suggestions:

1. Engage in open communication: Discuss your desire for your parents to spend quality time together and emphasize the benefits of a short trip for their well-being and relationship. Respectfully express your thoughts and concerns, while acknowledging the importance of adhering to Islamic principles.
2. Highlight safety measures: Research and present information about the safety measures and precautions your parents can take during the trip. This can include selecting reputable accommodations, choosing well-traveled destinations, and planning their itinerary with attention to safety and security.
3. Seek local advice: Consult with local religious leaders or scholars who can provide specific guidance on the permissibility of travel for Muslim women without a Mahram in your particular cultural and religious context. Their advice will carry more weight and can help address any concerns or reservations your dad may have.
4. Propose alternative solutions: If your dad remains hesitant about your mom traveling alone, suggest alternative options that still allow them to spend quality time together. This could include planning shorter trips, exploring local destinations, or considering group tours or travel with other trusted family members or friends.

Remember that each family and individual may have different interpretations and practices when it comes to Islamic teachings. It’s important to respect your family’s beliefs and engage in open and respectful dialogue to find a solution that aligns with your religious values while meeting the desires and needs of your parents.