Multiple visa reentry..

Hi friends..
Can anyone here guide me if you know about multiple visit visa. My mother in law has 1yr multiple visa and she came here in november and went to India already in december. Now my query is if she have to come saudi again can she use the same visa or will she require a new visa again?
Thanks..

You haven't given any details i.e. when was the visa issued and what is the expiry date of the visa?

If the visa is valid and not expired, she can come again on the same visa.  Expiry is as per Islamic calendar and not Gregorian - so measure one year by subtracting 10-11 days from the expiry date as per Gregorian calendar.