Just found out I'm expecting baby number three! Has anyone been able to fit 2 highbacks and some form of infant seat in the back? I do have a mifold that the eldest can use in the middle for short around the town journeys but for long journeys I'd prefer the eldest to be in a high back! I know the graco highback is the narrowest! Really really don't want to have to change the car as I'm probably going to have to leave my job. Any advice welcome! Thanks in advance!