Using variables in gulp-jade locals from other locals

Question

My problem is the following: I'm trying to refactor a website and to replace all strings into some variables so when I change a variable it changes across the whole website. However, here comes the issue:

I have data in multiple Json files and I get it like so with gulp:

var locals = {
// Content
someContent: require('../data/content-path.json'),
someOtherContent: require('../data/other-content-path.json'),
};

gulp.task('jade:pages', function() {
    return gulp.src(pages)
        .pipe(plumber())
        .pipe(jade({
            locals: locals
        })
        .on('error', notify.onError({
            title: 'Jade Error',
            message: '<%= error.message %>'
        })))
        .pipe(gulp.dest('dist'));
});

So I can easily access any key from Jade like so #{someContent.key1}.

However, if I want to use some key from my someContent in my someOtherContent it renders it as a string (not parsing a variable).

someContent

{
    "key1" : {
        "subkey1": "5",
        "subkey2": "9"
    },
    "key2":"<p>Some markup which parsed as html if desirable</p>",
}

someOtherContent

{
    "title": "#{someContent.key1.subkey1} some other text"
}

So it works perfectly if I just use it directly in Jade, but it can't parse such a reference if I use it as #{someOtherContent.title}, and it outputs exactly

"#{someContent.key1.subkey1} some other text"

when I want it to output this instead

"5 some other text"

What could I do here to make it work? Any help is really appreciated. Thank you everyone.