Hi,

I found Willy-O at Bodleian- Firth c12(293) and 2806 c15(136), Dublin, 1867. There are only two relevant stanzas:

As Mary lay sleeping, her true love came creeping
To her bed-chamber door so slow,
Saying rise up, lovely Mary,
For I am your own true Willy O.

Mary rose up and put on her clothes,
To her chamber door did go,
It's there she found her own true love
And his face as white as snow.


Two lines of the second stanza are found similarly in "I will Set my Ship:

Mary rose up and put on her clothes,
To her chamber door did go, [Willy-O]

There's not much of a connection between Willy-O and the two Irish variants of "Drowsy Sleeper" which are Henry's "Sweet Bann Water" and Shields' "The Cock Is Crowing."

Richie