Hi Pat
Yes, you can fit two adults and baby car seat in the back of the Captur. I have a 2014 TCE90 model and have on numerous occasions had my wife and sister-in-law in the back along with my daughter in her car seat. There isn't alot of room, but it is serviceable and fine for short journeys. If traveling for longer periods, then pulling over to stretch arms and legs, reposition oneself, is probably in order.