Since Joe and I have so much experience, let us give you our advice for parenting three children ages three and under: outsource most of it.
Have your sister, brother in law, and parents watch the older two kids while you take advantage of room service at the hospital and occasionally send the new baby with the nurse to the nursery for a couple of short spells of overnight sleep between feedings.
Granted, our advice will only work if like us, you only have about 36 hours of having three three and under. (Georgia turns four tomorrow.)
All kidding aside, the girls met their brother for the first time this morning, and it was so sweet. The pictures say more than I can put into words.

Their doll carriers were their gifts from Waylon.

June insisted that we keep removing layers, all the way down until Waylon's diaper was off.
Unfortunately, they had to cart Waylon away for the rest of Georgia and June's visit for some specifically timed medical tests, but all was not lost. We had big times going up and down in the mechanical bed.