When should I have my dad come to stay with us?

My husband is military so we live away from family. We are having my dad come out to watch our 6 year old daughter so that way husband can be with me the whole time in the hospital. I had my daughter at 36 weeks 5 days and that would put us at Thanksgiving week. But my due date is Dec 31 but we all think I'll go into labor early again. My dad wants to come the second week of Dec when I want him to be here Thanksgiving week. I just dont know and drs won't tell me anything but read on line if you have went into preterm labor your 3 times more likely for it to happen for your other pregnancies. What do you guys think and when would you have your parents come out to help with the other kids.