Jumping off of
@Willow Knight's post, re; JW setting up a baby monitor and baby bed, etc... I think we only have JW's word that he set up the baby bed/monitor, and he very well could be telling the truth, as he'd have probably remained as friendly as possible with all of the Rs/HHG.
A couple three types of baby monitors, that was available, w/apps, for cell phones, in 2016.
WiFi Baby | Baby Monitor Review | Best Baby Monitor App FAQ
Cloud Baby Monitor
...and, Dust off an old smart phone that you have
lying around -- you'll need two phones to pull this off. (And if you don't have an old phone, chances are you will soon considering how often new versions come out!) The good news is that you won't have to pay to use your old phone since you only need Internet access and it should work on the same Wi-Fi network you use with your current phone. Download the app of your choice onto both phones. Set up one in the nursery and point the camera at the crib. "
Try This Trick: Turn Your Phone Into a Baby Monitor
Finally, if he did set up a baby cam, that was similar to the above, and was kind enough to hook up the app on their cell phones, it could have been as simple as saying; I'll need your password to set this up, on your phone, and wifi..., then he'd have the info to set it up on his own cell, too. He could have done that right there, while he set up the monitor.