There has to be a way. I am sure people have done this in the past.Clarification of RO Credit based on Accompanying Canadian Citizen:
Odds are you misunderstood what you read (assuming you read a reliable source, like information published/posted by CIC/IRCC).
In particular, @scylla is correct. A Canadian PR has never been entitled to credit toward meeting the PR Residency Obligation for days outside Canada that they were accompanying their child who is a Canadian citizen.
Quoting directly from the statutory provision itself, RO credit based on accompanying a Canadian citizen is for days the PR is
"outside Canada accompanying a Canadian citizen who is their spouse or common-law partner or, in the case of a child, their parent"
. . . and to be clear, "in the case of a child" means a child who is a PR accompanying "their parent," when the parent is a Canadian citizen (and the PR meets the definition of a "child"). It has not been at all uncommon for some to misunderstand this to include credit for a parent abroad with their child who is a Canadian citizen but that is not what it says or means, and has never been interpreted otherwise in the IAD or Federal Courts, or in guides or instructions for IRCC/CIC or CBSA immigration officers.
To read the statute itself, see Section 28(2)(a)(ii) here: https://laws-lois.justice.gc.ca/eng/acts/I-2.5/page-5.html#h-274598
To see version adopted and in effect as of January 1, 2003, which for this provision is the same, see here: https://laws-lois.justice.gc.ca/eng/acts/I-2.5/section-28-20030101.html (version 2003-01-01 to 2005-03-31)
It is easy to navigate the various versions over the intervening years at that site; this particular provision has not changed.
Similarly in the applicable operational manual, ENF 23, dating back to its first version, 2003-09-02.
Further Clarification of RO Credit Based on Accompanying Canadian Citizen; Accompanying Citizen Spouse:
In the responses so far there is some dancing around the potential for a who-accompanied-whom question arising when a PR is relying on RO credit for days outside Canada based on the accompanying a Canadian citizen spouse. If, indeed, you are considered to be accompanying your PR spouse, not her accompanying you the Canadian citizen, that can result in NOT getting RO credit for days outside Canada together. BUT this does not appear to be common. BUT for many years now, in many IAD and Federal Court cases the IRCC Minister's representative has been arguing that RO credit should NOT be allowed for days the citizen spouse is accompanying the PR, rather than the PR accompanying the citizen.
So there is SOME risk unless it is clear that the couple moved abroad from Canada together and are living together abroad. How much risk will vary depending on the particular circumstances and, in particular, the extent of the risk is extremely difficult to quantify.
Discussed in depth here: https://www.canadavisa.com/canada-immigration-discussion-board/threads/who-accompanied-whom-can-matter-for-prs-living-with-citizen-spouse-abroad-update.579860/
If your PR card expires or about to expire and you are arriving by land and they let you in, can you stay in the country for two years and have PR card renewed?