My dog is a 180-ish pound Great Dane, almost 8 years old, and taller than my 4yo. Indeed, he can look up and lick my wife on the chin, regardless her not liking it. He's slept at the foot of our bed since the day we got him...and indeed has actively prevented the kids from falling off the bed back when they were babies 4 and 6 years ago. Perfect, enormous dog.
But he's out of time. We sleep on the top floor of a raised split-level, with 5-half stories from the basement to the top floor. Great Danes only live about 7 years...and as expected, the 8 year old horse of a dog is running out of juice in a typical Great Dane fashion. His hips are giving out. He falls down our stairs 1 day in 3, because his hips won't take him down properly...and can barely make it around the block any longer. My wife can't lift him...and he's slept downstairs for the last week. For the first time in his life, he's not with his family at night.
So, I called the vet today to schedule an appointment to put him out of his misery...next Tuesday. And now I'm crying over a stupid moose of a dog. Returning to your regularly scheduled programming sometime soon.