Can daughter fit in back seat? ('11/'12)

I sat in the back seat, with my salesman in the front seat when I was trying out the Mustang, and it does work well enough for my purposes. (5'10", 175lbs.) If I stretch up straight, my head can touch the roof, but I have to "try" to do it.

Frankly, I'd be more concerned about small kids in car seats, where their legs have to stick out straight! I would want to verify that their feet aren't into the front seat-backs.

My kids have more room behind me (and I am 6'5") in my 2012 GT than in my former 2001 Audi S4.

My 8 year daughter and 12 year old son have no problem sitting in the back of my '10. We have an SUV but the kids always want to take the Mustang. (I raised them right!)

I bought a Mustang because I have a daughter and didn't want a car that wasn't useful for anything.
I have a 6 year old and she fits there fine, as do I.
Once I went for a drive to go get some wheels/tires for my mazda 626 and forgot that I had my truck full of all my work equipment (which almost fills it), my daughter in the back seat and my gf in the passenger seat. I actually managed to put all the stuff from the trunk into the back seat next to my daughter and fit all 4 rims with tires into the trunk. Of course I am lucky they were 15" datsun wheels with 195s on them but still that's a lot of stuff to put in a mustang!
to me my Mustang is a "car" and as such it needs to do things that cars can do. As a daily driver its been in snow, ice, rain, mud, rough gravel roads and it needs to be able to take multiple people and things places. If I didn't need all that I could have bought a corvette or a viper.
Think of the Mustang's namesake, the horse version. It wasn't the biggest, it wasn't the fastest over short or long distances, and it wasn't the best looking. But it WAS one of the toughest and most versatile horses. I expect the same from the car.

My nine year old son and seven year old daughter ride just fine in the back of my 2008. I'm only five eight though, so that might have something to do with it. Right after I bought it, we squeezed them, plus my five foot tall wife on the hump in the back, and my ten year old in the front seat, as they all wanted to go for a ride and Momma didn't want any of the kids without a seat belt so she sacrificed...
It can be done

My kids fit just fine. I'm 6'2" and they are 6 and 8 and both on the taller side for their age. I do tend to sit a little closer to the steering wheel than most guys would my height. But probably no closer than anyone 5'11" to 6' would.

In the end, as others have stated here. My kids love riding in the thing. We have a Toyota Highlander as well and the kids always choose the mustangs over the SUV.

I've even sat in the back. It's nothing i would want to do for more than an hour, that's for sure, but as long as everyone is willing to work out the best for each rider, it's more than possible.

i have a 6 and 7 yr old (both girls) and we all fit fine in the mustang (2012 gt)

I have 9 year old and 12 year old boys....they fit in the back fine, though its getting tight.

The Stang is my wife's toy and they only ride back there for short trips usually.

They also sit in the back seat of my 72 Barracuda, which is just as tight...the Stang is "deeper" but leg room is about the same.....not a lot.

I am 6'3 , 275 and have the seat back all thw way on both cars. Leg room is better behind my wife who has the seat about halfway forward on either side she sits in.