I'm doing the Outcalts primarily, at least so far. I do have Rebecca and John.I have his name as Outcalt to make it easier to find, but I know the northern branch of the family changed the spelling to Outcelt.I got their names from Allen Donald Tallman's Outcalt website.I have 9 children listed for them, but don't have the definite birth dates that you do, nor anything on Rebecca's family.
Tallman has her parents as Jacob McLain and Elizabeth Wilson.
One of their direct descendants, Alice May Herron, d/o Mary Rebecca Outcalt who is d/o John and Rebecca, is buried inMountain View, Howell County, MO near Willow Springs, Howell Co., where my ggrandparents Peter (1829-1911)and Annice (Unknown) Outcalt (1829-?)lived the last 10 or so years before their deaths. I haven't been able to find their burial places even though I know where he died (found the will and the settlement thereof) but hope to get to Mountain View this summer to see if Peter and Annice are there too.
I'd be happy to exchange information with you, either here or by email.Both ways would be good; that way maybe someone else will see our messages here and have more information for us.
I have some McLeans in another of my lines that were in NC, and prior to that, Philadelphia in the 1700s then to Ulster, Ireland. Probably not the same line, but not impossible either.