We never did see Baby Jack during our early morning stint of e-sitting.
Son-in-law Hugh had to catch the 6AM flight from Burlington to get to a conference (been there, done that). He, Kate, and Jack stayed at Nerdville summer headquarters because it's relatively near the airport. Kate had to drive Hugh there early enough for security etc. "Don't wake Jack up," we (Mary) said. "We'll watch him."
"OK," Kate said after just a little persuasion. "Should I install the monitor in your room?" The monitor is the device on the left. The device on the right is the transmitter and it stays near Jack's crib. We hear everything Jack says or doesn't say from our room above his.
"One problem," Kate said, "you'll have to wake up to turn the monitor on when I leave."
"Why don't we just turn it on now?" I asked.
"You don't want to listen to us snore," Hugh explained tactfully. Just to test, I turned the monitor on when we went to bed. It gave the roaring sound that indicates that the transmitter is off.
At 4:15 our alarm went off and I turned the monitor on. Its green light told us that the transmitter was now active.
Jack burbled a few times and we woke up – even me. Nothing serious enough to require a trip downstairs. Next sound we heard was Kate coming back from the airport.
BTW, under Jack's mattress is a breathing alarm. We would have heard it go off through the monitor if he'd held his breath. He didn't.
Glad to learn about all the latest technology.