Fortunately I had dropped DD1 off at childcare before I went into labour but I had also arranged for both my mum and MIL to come and stay at our place when the time came. As it worked out DD2 arrived before DD1 had even finished her day at childcare so DP came home, picked her up along with my mum and MIL and brought them all to the hospital together - he refused to tell mum and MIL what we had until they got there as we thought DD1 should be the first to know by meeting her new sister

We also had contingencies though with next door neighbours and friends if we had to rush off in the middle of the night or before or mothers arrived as they both have a fair way to travel. So in total I think we had the main plan and 3 back up plans.