Biggest thing is keeping your eye on weather conditions.
The time I was angriest, as an adult at my sister, was when she had her second child.
My mother and I followed her husband to the hospital on the day they were to be discharged. It was rainy with the temperature dropping fast. At pretty much the last minute she decided she was going to take a nap before she want home. I tried to tell them about the bad weather. BIL also know as condescending Jacka** by my husband and my self ,laugh at me. I wanted to take her oldest child and my mom back to their place but she had a dream of them going home as a family.
My mom, to keep the peace, said it wasn't that bad yet so we had to go shopping until sister was done with her nap. I told them to hurry up as soon as we got back to the hospital.
The weather was getting as bad as I told them it would be and it was getting dark. Another hour and a half later sister was ready to go and the roads were glass and it was very dark. My mom and I were almost in a multi car pileup. BIL switched cars with me so I could drive the car with better traction. So for the next 3 hours I had to drive unfamiliar roads, during an ice storm, in the dark, with 2 babies, trying to calm down a woman who had just given birth, crying she has killed us all on a trip that would have only taken twenty minutes if everyone would have listened to me in the first place.