If a couple have marital relations then fall asleep and wake up at sehar time, if they start fasting at sehar time without gusl is their fast considered invalid?

If their fast is considered valid and the couple still haven't made gusl till Zohr (Dhohr) is their fast still considered valid?

In this situation what should the couple do?

Please explain in detail. Thank you..

If a couple have marital relations then fall asleep and wake up at sehar time, if they start fasting at sehar time without gusl is their fast considered invalid?

If their fast is considered valid and the couple still haven't made gusl till Zohr (Dhohr) is their fast still considered valid?

In this situation what should the couple do?

Please explain in detail.

If a couple have marital relations then fall asleep and wake up at sehar time, if they start fasting at sehar time without gusl is their fast considered invalid?

If their fast is considered valid and the couple still haven't made gusl till thur is their fast still considered valid?

In this situation what should the couple do?

Please explain in detail. Thank you..

If a couple have marital relations then fall asleep and wake up at sehar time, if they start fasting at sehar time without gusl is their fast considered invalid?

If their fast is considered valid and the couple still haven't made gusl till Zohr (Dhohr) is their fast still considered valid?

In this situation what should the couple do?

Please explain in detail. Thank you..