Keepin’ Score: Davey Jacobs is Older Than Jack Kelly and Here’s Why
As a general rule of thumb in Broadway scoring, younger characters sing higher than older characters when both are the same gender.
There are only two occasions in the show that Jack sings lower than Davey.
The first occasion is in Seize the Day when Jack comes in on the verse right before the dance break.
Jack and Davey are in unison for “Behold the brave battalion / That stands side-by-side / Too few in number / And too proud to hide.” Jack sings higher than Davey on “Then say to the others / Who did not follow through,” and they’re back in unison for “You’re still our brothers / And we will fight for you.” (Newsies Live script, page 41)
When we get to “Now is the time to seize the day / Stare down the odds and seize the day / Once we’ve begun / If we stand as one / Someday becomes somehow / And a prayer becomes a vow” (Newsies Live script, page 41) Jack sings the melody Davey has already established while Davey sings a higher counter melody. At this point, Jack is following Davey’s lead and singing what he’s just been “taught.”
The other instance is in Watch What Happens Reprise in the final chord on “we’re back.” (Newsies Live script, page 57) This time Jack is an octave down from Katherine, following her now while Davey sings a different harmony.
In conclusion, Jack and Davey might both be seventeen, but based on their vocals in the Broadway show, it’s safe to assume Jack is a few months to nearly a year younger than Davey is.