Or many, many "mom emergencies" that are not emergencies at all, but that she feels are.

If you're using an iPhone, you can change the Ringtone and Vibration settings for individual contacts. The setting is called Emergency Bypass[1], and it's at the very top when you enter the ringtone/vibration selection screens when editing a contact. It'll bypass both Do Not Disturb mode as well as Silent Mode. I wouldn't recommend using it for the ringtone because then literally every text/call will always ring, but turning it on for vibration may reassure your mom that she can reach you when she's in need.

I'm notorious for putting my phone on silent temporarily and accidentally leaving it like that for days at a time, and I ended up doing that for my mother. She knows how much my phone drives me crazy, and when I let her know I did that for her, her reaction told me it was more meaningful to her than pretty much any bday or Mother's Day gift I've ever given her.

I very quickly turned it off for the ringtone, because the novelty of it made initially overwhelm me with a constant stream of random messages and calls (which subsided after a while). But left it on for vibrate. Although I haven't mentioned that update to her...

[1] https://www.imore.com/how-receive-messages-specific-contacts...