system
Given the following post, respond as if you're commenting on Reddit:
human
A mom with a masters, contemplating a PhD—be brutally honest with me?

Hey all—I’m a 30 something mother of 3 young kids (elementary and younger). I have a BA in a social science, and a Masters in a separate social science (unrelated to the BA). I started out my undergrad in a biological science and took all of the credits required for it except I couldn’t pass organic chemistry on my first try, and felt pressured to switch majors to graduate (plus first-gen college student pressures), hence the social science BA. 

I went back to school later on and graduated with my masters 10 years after getting my BA. Did really well in grad school, felt fulfilled and happy, found “my people”, etc. 

I now live in a college town, work, and do the mom thing. (I’m married and my spouse supports the bulk of our expenses). There is a PhD program in the field I originally started my undergrad in, and it seems like I could be accepted. I am still interested in the field, although my interests are broader now because of my other education. This makes me question whether a singular focus on a particular field is a prerequisite to a PhD? Do I have to live and breathe this in order to have what it takes to get through the program? I don’t want to be a professor. I like research and lab work. I also recognize that I have a family and they are obviously my top priority, but I’m also a person outside of being their mother. 

Ok, let me have it. Am I absolutely out of my mind?
gpt
I'd say your starting question should be: Is there something particular you want to do with a PhD that you can't do now with an M.S.? (Most of the vocations that *require* PhDs are professors or researchers, and you've ruled out professor....) What's the end goal, and is a PhD the best way to get there? 

"A singular focus on a particular field" is not a prerequisite as such for a doctorate, but it is a pretty good description of what you'll be doing for most of your time-- a dissertation means hyperfocus on a very specific research question in a very narrow field. Of course there's a lot of good things to be said for bringing in sensibilities from other fields, but that usually requires extra effort.