Cross country move

So in 4 weeks my family will be moving from the East coast to the West coast. The drive, without kids, is only about 3-4 days. With kids, we're expecting it to take about 7 days. We have a 2.5 year old and a 7 weeks old (although when we move she'll be 11 weeks). I would just fly with the kids while my husband drives alone, but his grandmother wants to see the kids so we're driving to Kansas as a family at the very least. I need help as to how to keep my toddler busy during these long car rides. If my husband had his way we would drive for 10 hours a day, but I told him we had to stop every time I need to bf our newborn. Any advice as to what I should bring/prep?