What do you guys do stroller wise with a third baby?

I have 3 year old twins, and I’m 5 weeks pregnant. They will be 3.5 years old when the new baby is born. Do I need a triple stroller? Any ideas/advice? Will they be old enough to walk places? Should I just keep a double stroller? Any stroller recommendations that can accommodate a newborn and one or two 3.5 year old(s)?