Don't know if you still need this information, but there is a marriage listed on familysearch.org for a Lexie Swisshelm to a Claude Plummer. They were married on 1 Oct 1910 in Adams Co., Ohio.
Claude's parents are J. N. Plummer and Lydia Bradney, and he was born on 22 July 1892 in Adams Co., Ohio.
Lexie's parents are T. J. Swisshelm and Ida Garman, and she was born on 27 Apr 1892 in Adams Co., Ohio.
Here's the link to their marriage: https://familysearch.org/pal:/MM9.1.1/X8CF-SNX
They must have been divorced, because Claud Plummer remarried on 6 Nov 1915 in Hamilton Co., Ohio, to Cora Storer. Claud's parents are listed as Newton Plummer and Lida Bradley on that marriage certificate. Claude and his second wife Cora moved to Illinois by 1920, according to other records (a death record for one of their kids and a marriage record for another one) listed on familysearch.org.
There's also one listing for a child of theirs on that site. Myron A. Plummer, b. 7 Jan 1911 in Ohio, d. 23 July 1913 in Franklin Twp., Adams Co., Ohio. He was buried at Locust Grove. (Lexie is the informant on his death certificate, and put "Miss Lexie Swisshelm", not her married name, on that line.)
Here's a link to Myron's death record: https://familysearch.org/pal:/MM9.1.1/X86R-2WL
And there's one child by Lexie's second husband who also preceded your grandma. That was an unnamed male Newman, who was a premature birth. He was born and died on 5 June 1919 in Meigs Twp., Adams Co., Ohio. He was buried at Newman Cemetery. Here's the link to his record: https://familysearch.org/pal:/MM9.1.1/X828-KX5