I’ve been discussing the descendants of Thomas Casbon (~1743-1799) of Meldreth (see Stepping back: Thomas Casbon, 1743-1799). Thomas’ youngest child was John, baptized Casborne October 3, 1779 in Meldreth.  He was the third son named John, the first two having died in infancy.
For review, here is a diagram of Thomas’ children
John married Martha Wagstaff December 29, 1802 in Meldreth. 
The record tells us that John and Martha were both single (i.e., not previously married), and they both belonged to the Meldreth parish. Also, John was able to sign his name. Martha signed with her “mark.”
Martha was baptized as Patty Wagstaffe 1775 in the little village of Cockayne Hatley in Bedfordshire, about 7 ½ miles west of Meldreth and just across the Cambridgeshire county line.  How I came to learn that Martha and Patty were the same person is an interesting and convoluted story that I’ll save for another day.
For reasons unknown, John and Martha did not remain in Meldreth. But they didn’t move far. Their first two children were born in the town of Royston, a sizeable crossroads and market town a few miles south of Meldreth, in Hertfordshire. These children were: Jane, baptized November 27, 1803, and William, baptized on Christmas Day, 1805. , Edith, their third child, was baptized in the village of Whaddon, about 1 ¾ miles west of Meldreth. 
Composite image showing baptismal records for Jane, William, and Edith Casbon (Click on image to enlarge)
All three children lived well into adulthood and remained in the Meldreth area. Their stories are interesting enough to warrant their own posts.
John, however, did not live long after his children were born. He was buried at Meldreth December 3, 1813, leaving Martha a widow with three children. 
Martha married Samuel Barns, a recent widower with his own children, July 24, 1815 in Meldreth.  Due to the high death rate and the necessity for both a breadwinner and someone to watch the children, remarriage was a common and practical method to restore two parents to broken families.