Can a Porsche 911 Carrera or Turbo be a family car?

Sure they can.  They just can't be a really good family car.

You're right, technically they can seat 4 people.  And as long as 3 of those people are both a) midgets and b) extremely friendly with each other, they might just be seated comfortably.  Anyone else is going to need a dozen sessions with a chiropractor after sitting in those cars.

THAT is why there is AUDI cars! They  are KIN to PORSCHE as is VW, BENTLEY, BUGATTI, SEAT< and SKODA! I owned TWO AUDIS and there is NOTHING LIKE THEM! SO precise! So THRILLING! So FLAWLESS in the BRAKES and SUSPENSION and COUSIN to PORSCHE as well! I LOVED the porsche 911 AFTER it became a FOUR WHEEL DRIVER! AUDI had QUATRO longer than ANYONE else except for VERY OLD JEEPS< that were LIKE QUATTRO but NOT as efficient! Then there is SUBARU ! The PANAMERA is UNREAL but very PRICEY and is ALSO a FMILY type car! You are BEST off with an AUDI QUATTRO TURBO suv for ROOM and COMFORT! BYE NOW!

My kids were fine in my 911 Targa until they were about 9.  After that.....Not so good !

they seat 4 people but not as comfortable as a normal family car...

What ever dude.

I think they really seat only 2, you would need to put the front seats forward to allow enough leg room for 2 passengers to sit in the back. If the front seat passengers were very small in stature that might be possible but would be really uncomfortable for most people. The luggage space is very small, families with kids tend to carry a lot of stuff and buy a lot of groceries and shopping, you would have to make 2 trips to fit all that stuff in. Most families that have a Porsche also have an SUV for the regular stuff like driving the kids to school.