Driving 6 hours with a baby

So I just had a baby and I’m still in my six weeks. My husband parents brought us a car seat(we already have one for my car) so we can put in his car. But they said they can’t ship it because it cost $60 to ship to us and they can’t afford it. We live 6 hours north from them. They want us to come down with our baby once my 6 weeks is up to come get the car seat. I’m not comfortable with it because that’s a long drive and plus we have a baby. I told my husband I’ll think about it…. Idk what to do. Any advice?