Multiple entry visa-one year

Recently i got my wife to Saudi Arabia on a Family visit multiple entry visa-one year, She stayed one month and left Saudi Arabia on the 28th December 2019, My question is that does she have stay a certain waiting period example like 3 months before she could enter Saudi Arabia again. Her visa expires on the 4th of November 2020 . Please anyone advice.

No waiting period.  She can literally leave and come back the next day.