Given the following context:

Santamental, released in October 2003, is a collaborative project featuring several prominent musicians such as guitarists Eddie Van Halen, Slash, Steve Vai, and drummer Gregg Bissonette. When Lukather's record company, Bop City Records, approached him about recording a Christmas album, he responded with a quip about his suitability for the project. The company wanted him to do the record knowing he would approach the project with a unique angle and produce something different from the typical Christmas album. Lukather recruited keyboardist Jeff Babko and guitarist Larry Carlton, who Lukather had worked with previously, to help arrange the songs. The project was a challenge to Lukather, who had to be creative to turn the traditionally simple songs into something interesting for listeners without altering the fundamental structures. He said of the album, "But I never dreamt in a million years that I'd do a Christmas record."The musicians Lukather chose for Santamental, most of whom were involved in the hard-rock genre, lent a heavy feel to the album. Van Halen recorded guitar tracks for "Joy to the World" after not having been in the studio for some time but immediately made an impression on Lukather with his level of playing. Vai provided guitar work for "Carol of the Bells" along with Lukather's son Trevor, then 14 years old. Slash, who recorded his part in one take, played on the Lukather/Stan Lynch composition "Broken Heart for Christmas". Lukather spoke highly of Slash after the project, calling him the "Keith Richards of our generation". Well-known session guitarist Michael Landau played on the song "Look Out For Angels", and there is a version of "Jingle Bells" featuring a big band and sung by Sammy Davis, Jr. Santamental was recorded in six days, after which Lukather proclaimed it "his first and last Christmas album".

answer the following question:

What is the first name of the person who provided guitar work for "Carol of the Bells" along with Lukather's son Trevor, then 14 years old? 

Steve