mg, here's the passage...

From O'Neill's "Irish Minstrels and Musicians; The Story of Irish Music":

Cornelius Lyons

   This renowned musician, who in his day was household harper to the Earl of Antrim, was a native of County Kerry, and flourished in the latter part of the seventeenth and the early part of the eighteenth centuries.
   Agreeable in personality, his reputation both as a man and a musician was admirable. Though a rival in art and even composition, Lyons was O'Carolan's loyal friend and companion. Famous as an arranger of variations in more modern style to such airs as "Eileen a Roon", "The Coolin", etc., only one of his original compositions has been preserved.
   The Earl of Antrim was a wit and a poet, and notwithstanding his rank was quite democratic in his manners. Once while in London accompanied by Lyons, they went to the house of a famous Irish harper named Heffernan, who kept a tavern there, but agreed on a plan before entering.
   "I will call you cousin Burke," said his Lordship. "You may call me cousin Randall or My Lord as you please." It was not long before Heffernan was made aware of the dignity of his guest, from the conversation and livery of his lordship's servants. Heffernan being requested to bring his harp complied and played a good many tunes in grand style. The Earl then called upon his "Cousin Burke" to play a tune. After many apologies and with apparant reluctance the supposed cousin at length took the harp and played some of his best airs. Heffernan after listening a while started up and exclaimed, "My lord you may call him cousin Burke or what cousin you please, but Dar Dia he plays upon Lyons' fingers." (pg. 63)

He's also mentioned as the teacher of the County Louth-native harpist, Echlin O'Cahan (Ackland Kane), and later named as "Con" Lyons, the teacher of the northern harper Hugh Quinn, "A gentleman's son, and as such conducted himself."

Thankfully, there's no mention of Con Lyons (or perhaps a daughter) feeding McDonnell green 'n yaller eels at any time, so yer prospective kin's off the hook there.