The ruling on fasting on Friday while fasting on the day before or after it

The questioner is from Yemen and resides in the Kingdom, and his name is symbolized by (M. S. M). He says: My question, O honorable Shaykh! By the grace of Allah , I fast on Mondays and Thursdays of every week, and, if Allah wills, I intend to fast three days of every month. But if the 13th of the month falls on a Thursday, the 14th on a Friday, and the 15th on a Saturday, is it permissible for me to fast on Friday? Please advise us, may you be rewarded.
The answer: Yes, fast it; because it is attached to another day. What is prohibited is fasting it alone. As for fasting it with Thursday or with Saturday, there is no harm in that. Yes. And praise be to Allah. Yes.