I often turn on 'Do Not Disturb' mode, especially at night. I would like a few specific phone numbers to be able to bypass the Do Not Disturb if they call me, so that I can be altered in case of emergency. Is there any way to do it?
You should be able to set an exception rule to allow calls and texts from certain people (All/Contacts/Favorites). Different manufacturers will have different set ups but you should be able to get to this setting by going
Settings > Sound & notification > Do Not Disturb > Exceptions
You may need to turn on Do Not Disturb to alter these settings.