From my perspective:
When I was a kid, Christmas morning went like this: one of us kids would wake up and then they'd wake up the other kids. We'd all get together and go to Mom and Dad's room to wake them up, too. Mom would keep us all contained in the kitchen, while Dad would call the grandparents. We weren't allowed to see our gifts until all of the grandparents were in our house. Unfortunately, one set of grandparents lived about 30 minutes away. So, Mom and Dad would keep us corralled in the kitchen, just inches away from the paradise that Santa had set up in our den. After what seemed like hours, all of the grandparents were accounted for. At this point, Dad would say "Let me go see if Santa Claus came" and he'd tip-toe down the hall and take a look into the den. From there he'd shout: "He came, he came!" and that was our green flag that it was ok to cross the boundary lines that were previously set.
The same year, from my Dad's perspective:
We had supper with Harriet's side of the family, followed by a three hour long gift-opening marathon! The kids looked tired, but Harriet insisted that we take them to the candle light service at church. We finally got back home around midnight and got the kids to bed fairly easily. Once we were sure that they were asleep, I went next door to the VanDyke's to retrieve all of the Santa gifts from their basement. We had stored everything in their basement and the plan was that they would leave the basement door unlocked. In their haste to leave town, the VanDyke's had forgotten the plan. I ended up having to break a window to gain entry. Thank God this was in the days before home alram systems! Once I got into their basement, it only took about twenty trips to get everything back to our house, and by 2am we were ready to start setting up the toys. We drank spiked eggnog as we unpacked all of the boxes. Harriet filled the Christmas stockings as I tried to assemble an electric train set- the directions were in Chinese, so I wasn't having much luck. After a few hours, the train was complete and it was time to move on to the rest of the gifts. We made 3 piles- one for each of the boys. As the sun began to rise, we finished off the last of the eggnog and groggily tip-toed past the boy's rooms and pored ourselves in the bed. My eyes weren't even closed before the kids were awake and ready to go. I made the calls to the grandparents as Harriet made a pot of coffee. It's a shame they didn't have RedBull back then! We needed all of the caffeine we could get to stay awake and try to not appear too drunk when the grandparents arrived. Luckily my parents lived across town, so by the time they arrived we had had a couple of cups of joe and brushed our teeth and no one would've ever guessed that we'd pulled an all night drinking binge while we assembled the Santa Clause gifts. Just before it was time for the kids to see their gifts, I remembered the eggnog glasses and the ashtrays on the coffee table. The grandparents were strictly Southern Baptist and they would not have approved, so I made up an excuse that I needed to go see if Santa had come. I snuck into the den and stashed the glasses & ashtray under the sofa. I scanned the room to make sure there was no evidence of the previous night's drunkfest and when I was satisfied, I announced "He came, he came" and the family piled into the den.