Keep the coupe, get rid of the others and get a M. The back seat in a G sedan isn't that big.

Although, as much as you resist .... you will need a Mini-Van or SUV. You have to haul so much crap with kids regardless if you are going for 1 hr or 1 week.

 

I have a 4YO and 2YO and recently purchased the Coupe since we have an SUV as the primary family vehicle. Clearly the Coupe would not be the ideal choice for hauling the kids around several times a day, but it works for the occasional trip without being much of a hassle.

My 4YO uses a booster seat and my 2YO has a forward facing car seat. My 4YO loves riding in the car so I have used it for driving the kids more than I originally planned, but it really is not a major issue. The seat moves forward far enough to make loading/unloading fairly easy. I do have the seat a few inches further forward with the kids in the car, but it's not a big deal for short trips (I would not drive across the country with the kids in back).

My recommendation would be to keep the coupe.

 

I have a 13 and 10 year old and they both love the coupe along with my wife. We also have 2 other vehicles that can fit the family so the coupe is primarily my "date" night and weekend car along with work occasionally. For bigger trips we take the SUV. If it is just 2-3 of us the coupe is great otherwise gets a little crowded. Since you have another DD I would keep it.

 

Reading through this thread is scaring me lol. Luckily I'm only 22 so i don't have to trade in my coupe for a long time