Other information I have found gives Letitia's birth as about 1870 which would make her 30 years of age at the time William, her first child was born which I find very hard to believe.  Thomas, her last born arrived in 1829, she would have been 60 years of age, again pretty hard to swallow.  My belief is William married a younger woman after the death of his first wife and using the dates of birth of her children I feel a much better "guess" would be Letitia was born circa 1785.