Who were Meriwether Lewis's sister and brother?

Lucy Meriwether married William Lewis, who died in 1779 and then re-married to Captain John Marks six months later.
To William Lewis she gave birth to:
Jane Meriwether Anderson
Meriwether Lewis
Lucinda Lewis (who died in childhood)
Dr. Reuben Lewis

To Capt. John Marks she gave birth to:
John Marks, Jr.
Mary Garland Marks.

John and Anne Rogers Clark had ten children, six sons and four daughters:
Gen. Jonathan Clark
George Rogers Clark
William Clark
Anne Clark
Capt. John Clark
Lieutenant Richard Clark
Capt. Edmund Clark
Lucy Clark
Elizabeth Clark
Frances Eleanor Clark