Philanda Elkins Risdon... Who was she?

One of my most elusive Female Ancestors of all time is this 4x Great-Grandmother.

Philanda Elkins (or could it be Perkins?) was born sometime in the later 1810s, I think circa 1816-1818... probably in Vermont?   In addition to not knowing her last name for certain – the spelling of her first name has nearly never been spelled the same way twice – though for the time being and for the sake of space, I’ve adapted Philanda… She did have a granddaughter born with that spelling, so it seems a likelier option than Filinda or other variations.

She was married sometime prior to 1835 to Harley (Harla) Risdon, probably someplace in Vermont... They would go on to live in various places, but were in Erie, New York for a time.

By 1860, the Risdon family had relocated to Putnam County, Illinois and their children included, but are not lmited to, Harl, Caroline “Carrie” Bruce, Almond, George (died in Civil War), Leroy (died young?), Henrietta Ross, Lydia Buckingham, Oscar & Susan Lemira “Lea” Walker.

Incidentally, in the 1860 census, Harley Risdon is listed as “pauper” – I assume this to mean there was little money – and by  1870 Harley is no longer with the family – at 70 years of age, I assume him to be deceased.

At this time the Risdon children are found in various places… some married and on their own, others living with siblings and some as “servants” in other households.  Others, like George & possibly Leroy are deceased.

To add to the mystery, in 1870 there is a second  Philanda Risdon of similar age living in a neighboring county! This second Philanda eventually married Elijah Pomeroy and remains living in LaSalle County, at least through 1880.

My Philanda is gone from Putnam County after 1870. I’ve tried to trace the origins of the second Philanda Risdon, but she appears to have dropped from the sky.

It’s possible that my Philanda was incorrectly included in the 1870 Putnam County Census – or was visiting at the time – and then also made the same census for neighboring LaSalle County as well—stories such as this are certainly not unheard of.

I’ve traced the Risdon descendants forward – in hopes of finding fellow descendants—it seems only Harl, Carrie, & Lea made it to “old age”, as they are the only ones living beyond 1900… though I don’t have proof of death for most of them – so anything is possible.

Who was Philanda Risdon? Was she an Elkins or a Perkins? Are the two 1870 Philanda’s actually the same person? And regardless, what happened to either of them after 1870/1880?

After 20 years of research,  I have more questions than answers – I’d love to connect with any Risdon researchers out there and anyone familiar with the Elkins name.