Even as a Green Card holder, and even with a re-entry permit, with her having been outside of the U.S. for more than six months, upon attempting re-entry she should be prepared to produce documents that she can use do support her claim that she was a student while outside of the U.S. and that she maintained a permanent residence within the United States.

Also, even with LPR status, if she had a prior history of overstay of unlawful presence, that history may result in her being found inadmissible even though she has a reentry permit. If that may be an issue she should consult an immigration lawyer.