Caring With Control

I've been a nurse for over a decade now, and I have a secret that's as fulfilling as it is unconventional. About three years ago, I started taking on a role beyond just healthcare for one of my patients, a man in his late 50s named Robert who suffers from mild cognitive impairment due to aging. We developed an agreement where he would refer to me as 'Mom' and respect certain boundaries set by our sessions. In exchange, I offer him guidance, support, and a sense of stability that seems to greatly benefit his daily life. It began with simple reminders about medication schedules and appointments but quickly evolved into setting strict bedtimes and wake times, ensuring he gets the rest needed for better cognitive function. There are moments when I feel like an authoritarian figure, which is quite a change from my professional demeanor at work. Robert even insists on calling me 'Mom' in public settings now, which initially made me uncomfortable but has grown to be rewarding. I'm not sure if this dynamic fits within the realm of normal DDLG relationships or if it's just an extension of my caregiving role gone a bit further than professional boundaries suggest. What do you all think? Is this common for someone in my position?