If you read the last bit of info, JDL's marriage certificate states he married Elizabeth Doyle Reed, but her father's name is John Doyle.  I have a theory...  I think she must have been married prior to her marriage to JDL.  In the info found on johndleegenealogy.blogspot.com it says -

My mother had two children by my father -- that is William Oliver and myself.
Since Ralph and Elizabeth were married on 26 February 1811, it is highly unlikely that John D. Lee had an older brother whose father was Ralph Lee. The earliest William Oliver could be born legitimately would be in December 1811 and Elizabeth would have to get pregnant immediately to have John D. on the 12th of September, 1812. In addition, no child of Ralph and Elizabeth was baptized near this time.

John D. Lee gives three children for his mother, a girl and two boys. In Kaskaskia church records there are three baptisms for children of Elizabeth or Eliza Doyle, a girl and two boys.

In the archives of the Catholic church in Belleville, there was a baptism for a Benjamin Rode, on Jan 29, 1809, with parents Jean/John [Rode] and Elizabeth Daille/Doyle. The child was born the 27th of January.

I am wondering if Rode is another way of saying Reed (since they were French, maybe it was slightly altered in translation, since Daille and Doyle were interchanged as well), therefore, maybe this is our Elizabeth Doyle and maybe she had this first child before marrying JDL.  Just my thoughts.  They could have even changed the boy's name so as not to point to the fact that it was possibly an illegitimate child, or from another father.  Sounds far fetched, but maybe true.

-Info from Mandi