Traveling 8 hrs in a car with frozen breastmilk

Hello ladies, my husband and I did a baecation without any kids and our LO is 10 weeks old 😢. I supplement with formula or pumped milk at times I am away from him. This trip is 5 nights 😮 we needed this desperately for his sanity and our marriage. I’m MISS MY BABY!!! 😰 anyway back on topic. I will be trying to pump just about as much as I breastfeed. This will be my opportunity to build a stash. There is a full side by side in our vacation condo so no trouble there. I do not want to waste all this liquid goals what is the best way to travel in the car back home with my frozen milk. Any recommendations on coolers or methods to packing the cooler?