I seriously doubt the accuracy of the family tree on Ancestry which gives Robert Corlett's parents as Robert Corlett and Ann Southward.

If the birthdate on the gravestone (at Findagrave.com) is accurate, then the Robert, son of Robert and Ann Southward, christened at Lonan in 1836 (see Familysearch,org for children of Robert Corlett and Ann Southward) is not the same. The family is listed in the 1851 census at Laxey Glen, Lonan, (see Ancestry.com, census records) with a son Robert age 14, which pretty well confirms the 1836 birth date.

I suggest you look for an obituary for Robert Corlett (try the Kankakee public library, genealogy section), and/or obituaries for Robert's children--in particular the one which leads to your husband.

Good luck

Lois