Head First - S1-E6
Revealing mistake: When Doug is making breakfast it's clear there is no flame coming from the gas hob. (00:08:15)
Revealing mistake: When Carrie knocks the cards over at the start, some stay in the pyramid shape despite being knocked over, revealing the cards are glued together. (00:03:15)
Revealing mistake: When Carrie is talking about going to the fertility clinic, you can see the fridge behind Doug through the door. If you look closely just before the camera changes a boom shadow moves across the fridge. (00:01:35)
Queasy Rider - S2-E1
Revealing mistake: We see Doug crash into the fridge 3 times, thus implying that it's 3 times he's crashed. However it is the same clip used for all 3 crashes. (00:13:40)
Revealing mistake: During both opening and closing driving scenes, a light on the back and top of Doug and Carrie's heads slowly flickers on and off but never moves - revealing a stage light simulating driving past street lights. (00:00:20)
Revealing mistake: When Doug snaps his bat it's very clear it is pre-broken. (Possibly from a previous take or to make it easier for Kevin James.) (00:07:55)
Revealing mistake: When driving to find the dog, neither Doug nor Carrie's hair is blowing in the wind - even when they're on the back of the convertible. (00:18:00)
Revealing mistake: When Doug and the rest are at a ballgame, the man sitting behind them is eating a hot dog. Actually he's pretending to eat, it never shows any bite marks and the guy is pretending to chew it.
Revealing mistake: When the screen says "2 months later" the camera shakes. (00:21:20)
Revealing mistake: During the scene when Doug is "out with the boys" driving in Spence's car, you can tell they are actually in a studio using a green-screen because the stage lights reflecting off the car don't move. (00:36:00 - 00:36:35)
Frozen Pop - S2-E15
Revealing mistake: When Doug goes out to scrape frost off the car, we can see he casts 2 shadows from different stage lights as he comes down the steps as well as on the hood of the car. (00:01:00)
Revealing mistake: In the kitchen, Deacon asks Doug, "Are we gunna play basketball or what?" while leaning against the counter. In this shot you can see the kitchen wall is on an angle slanting away from the camera. This makes the kitchen look bigger and cuts down on the empty stage space on the wall where the cameras are. (00:07:00)
Revealing mistake: Both times when you see an overview of the bridge, it's the same clip being used. (00:07:10)
Revealing mistake: When Doug tells Arthur his toast is done, there is no smoke, but as soon as he is finished speaking there is smoke coming from the toaster. (00:04:05)
Answer: To answer the question directly. Carrie and Doug do not have a biological child during the show's main run. In season 3 or 4 finale (cant remember which) Carrie has a miscarriage. Later on in the show they find out Carrie has 1 working ovary. Thus reducing the chance of them conceiving. By the final season, they couple agree to adopt from China and go to collect their child in the show's final episode. While on the flight back from China it's revealed that Carrie is once again pregnant. However the last scene of the show is a flash forward showing that Carrie goes full term with that child and they are struggling with both kids.
Ssiscool ★