Parent PLUS loan on graduated plan or consolidate?

Hello all!

As of today I have around $39k in student loans. Of the $39k, around $17k are in my name and around $21k in 3 parent PLUS loans in my mom's name. All of the loans in my name are a mix of unsubsidized and subsidized loans and are currently in deferment. I qualify for PSLF and have worked full time for non profits since I graduated in 2019. I am in the process of finally certifying my employment at the non profits and get on an income driven plan to qualify for PSLF. I am also now in grad school part time and paying out of pocket to avoid loans with assistance from scholarships, fellowship, and working full time. Now the tricky part with my parent Plus loan…

While in school, I am paying on my parent PLUS loans which are in my mom's name. It was always an agreement that I would pay on them. The $21k of parent PLUS loans are currently in the graduated repayment plan and the payment is around $262 a month which I can afford. The tricky part is that my mom has additional parent PLUS loans that she took out for my younger sister's education when she started college in 2020. My sister's parent PLUS loans total nearly $100,000 and her interest rates are between 7.5% and 8%.

I am trying to figure out my options and the best route to take for repayment. Ultimately I'd like to have the lowest possible payment a month so I can continue to comfortably afford paying for my grad school tuition along with other expenses. My partner and I have also floated the idea of knocking out the parent plus loans sooner rather than later since they are not on an income driven plan nor do they qualify for PSLF since my mom has never worked for a qualified employer and she was laid off recently.

My mom and I are unsure if we should consolidate them now or stay on the graduated repayment plan. Or if there's an option to pick and choose which loans she wants to consolidate. From my limited understanding I do not think that consolidation would be in my benefit. My sister and I are paying off our parent PLUS loans in different ways. My sister is trying to pay off hers in chunks and as fast as she can. I am trying to pay the minimum until I graduate and my income increases. Consolidation would also increase my interest rate because they would be combined with my sister's loans. Additionally, we may benefit from the lower monthly rate now since my mom is on unemployment, however, (hoping she finds a job similar to her previous one) then it would be based on that income. My mom previously made around $75k. I am open to consolidation of all the loans if it would be fair and beneficial to both my sister and I for repayment. Please let me know if I have anything wrong as I am still learning and trying to become more financially literate. Below I have my loans and interest rates listed.

My Parent Plus Loans (in my mom's name)-All are Direct Parent PLUS and on Graduated Repayment Plan- Ends 01/21/2027 and then higher payment begins

1. $11,766.83 with 6.590% interest rate

2. $8,625.79 with 6.060% interest rate

3. $8,866.24 with 6.750% interest rate