The index to Ancestry.com's database of family trees shows a Beggs Family Tree with William Arthur Beggs, born 1871, died Missouri, son of Alexander Beggs and ---- Bridges. The submitter's source should be checked before accepting this as correct.
The 1870 Johnson Co IL census shows Alex and "Apsel" had a son named Louis, age 14. So if William Arthur was their son, too, then W. A. Beggs of Morley would have been the informant on Louis' death certificate because he was his brother rather than son. Censuses indicate Louis probably wasn't more than 17 years older than William. I can't find Alex's household in 1880. He's supposed to have died in Johnson Co in 1889.
William (listed as b May 1873) and wife Mary M. (Mar 1882, age 18) appear in the Scott Co MO 1900 census in Morley Twp with daughter Ethel (Oct 1899). On the previous page was the family of Lewis Biggs (b Dec 1856).
Isaac Beggs, b 1851 Johnson Co IL, d 1911 Kelso, Scott Co MO, was son of John H. Beggs. Illinois mrg index shows John "N." "Boggs" m Susannah Bridges in Johnson Co 23 Aug 1855. John H. and Susan (age 38) were one household away from Alex and Apsel in the 1870 Johnson Co census. Son Ike was listed as 18. Place of Isaac's burial was "Cypress" [Johnson Co] IL.
A WorldConnect Project submission states Alex and John H. were brothers. A list of children of John and Elizabeth Bridges shows Apsilla had a sister named Susan, b ca 1835.