Hi,
My mother had migrated to Canada (as a permanent resident) in 1993 or 1994 but only spent 6 months before returning home due to unstable care for her children. Upon sorting out issues and making attempts to return, there were issues with accommodation.
Over twenty years later, she is interested in visiting and perhaps regaining her PR status.
What are the steps to get this started?
She cannot regain her PR status. Either she is still a PR or she lost PR at some point over the last 25 years - in which case she would need to reapply from scratch. Has she been to Canada at all in the last 25 years?
Assuming she is still a PR, she would need to successfully re-enter Canada without being reported for failing to meet the residency requirement and then remain in Canada for 2 years straight without leaving. Only once she has lived in Canada for 2 straight years will she be able to renew her PR card and safeguard her PR status. During those two years, it may be difficult / not possible for her to access free health care since she has been outside of Canada for so long - so that's something to factor into the decision.
To enter Canada, she will need to travel to the US (if she's not there already) and then re-enter Canada through a land border. She cannot fly to Canada directly. When she enters Canada by land, it's possible she may not be reported by CBSA. In that case she can live in Canada for 2 years and then apply to renew her PR card. If she is reported at the border for failing to meet the residency requirement, she will have to appear at a hearing and should expect to lose her PR status officially and be ordered to leave Canada for failing to meet RO.
So not an easy process and no guarantee of success. But she can certainly try. First step is to obtain a US visa (unless she already lives here or has a valid visa to travel there).