Wendell Miller's first wife (who was the mother of John Philip) - her name is unknown. Christina was Wendell Miller's second wife.
John Philip and his wife Sybilla Fisher are both buried at Organ Lutheran Church.
John Philip and Sybilla did have a child named Catherine who was born 24 Oct 1789 and died 3 Oct 1839. Catherine married Dawalt Lentz on 18 Jan 1811. Catherine Miller Lentz is also buried at Organ Lutheran. There is no record in the Wendell Miller book of her marrying a Shelton.
What documentation do you have showing she married David Shelton?