Finding an AWS JavaScript Lambda module regardless of whether the lambda is hot or cold

AWS Lambda here (Node 16.x/JavaScript). I have the following project directory structure:

my-lambda/
  src/
    common/
      simple.js
    lambda/
      index.js <-- entry point for lambda

Where common.simple.js is:

module.exports.soSimple = function() {

  console.log("doing some simple stuff...");

};

And where lambda/index.js is:

exports.checkHealth = async (event) => {

    soSimple = require('../common').soSimple;

    let response = {};

    try {

        soSimple();

        response = {
            statusCode: 200,
            body: JSON.stringify(items)
        };

    } catch (e) {
        response = {
            statusCode: 400,
            body: "Unable to do even the simplest of things"
        };
    }

    console.info(`response from: ${event.path} statusCode: ${response.statusCode} body: ${response.body}`);
    return response;

}

When I deploy this Lambda and hit the API Gateway sitting in front of it, I get back a 502 from the gateway. When I look at the Lambda logs, I see:

{
    "errorType": "Error",
    "errorMessage": "Cannot find module '../common'nRequire stack:n- /var/task/src/lambda/index.jsn- /var/runtime/index.mjs",
    "code": "MODULE_NOT_FOUND",
    "requireStack": [
        "/var/task/src/lambda/index.js",
        "/var/runtime/index.mjs"
    ],
    "stack": [
        "Error: Cannot find module '../common'",
        "Require stack:",
        "- /var/task/src/lambda/index.js",
        "- /var/runtime/index.mjs",
        "    at Function.Module._resolveFilename (node:internal/modules/cjs/loader:995:15)",
        "    at Function.Module._load (node:internal/modules/cjs/loader:841:27)",
        "    at Module.require (node:internal/modules/cjs/loader:1067:19)",
        "    at require (node:internal/modules/cjs/helpers:103:18)",
        "    at Runtime.exports.checkHealth [as handler] (/var/task/src/lambda/index.js:3:25)",
        "    at Runtime.handleOnceNonStreaming (file:///var/runtime/index.mjs:1085:29)"
    ]
}

What do I need to do in the code (without changing the file/folder structure) so that common/simple.js#soSimple can be used inside my Lambda event handler when the Lambda is running both warm and cold?