@southtexas I have forgotten to take other meds but never the prednisone when my PMR was active. Mr Ugly always reminded me to take it in the mornings 🙂 There were a few times when I was almost off of prednisone that it would have been easy to forget taking my morning dose. Here's some information from Mayo Clinic on your question:

"If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses."
--- Prednisone (oral route): https://www.mayoclinic.org/drugs-supplements/prednisone-oral-route/proper-use/drg-20075269

Thinking that may be a good sign if you forgot to take a days dose and you weren't in a lot of pain. How is your pain level after you forgot to take a dose?