Advice re pension entitlements

Hi
Just looking for some advice! For the last number of years my sister has worked part time (20 hours per week). Occasionally she works extra hours to cover holidays etc. She doesn't generally pay much if any tax as she doesn't fall into the tax net. Some months PRSI contributions are deducted from her payslip and other times not as her total hours can vary month to month. However her employers contributions are paid every month. Her concern is if she isn't paying PRSI every month how will this affect her pension entitlements when the time comes. Will she still get her full contributory pension or how does that work? She is single with no dependents.
Thanks in advance for advice!

What class PRSI is she on? See here for details of what benefits are covered by the different PRSI classes.

As she is employed for 20 hours per week I assume her employer is paying a class A contribution on her behalf therefore she has the same entitlement to pension as any full time worker.
She can always check that on her P60 each year where it shows the number of insurable weeks, the number of contributions made, and the Class of those contributions.
Pension entitlement is based on the total number of PRSI payments made divided by the total number of years from starting work to age 65/66, to give a yearly average. (This is the basic simplified version and there are other factors)

Thanks Clubman and Blacksheep for your replies. On her P60 her PRSI class is AX - I don't know if that makes any difference. I presume she still retains her pension entitlements which is her main concern.

As long as the letter A is on her PRSI contributions it does not matter which letter follows that. All class A contributions are reckonable for pension purposes