Are there any modern-day equivalents or descendants of the job of knocker-upper?

Yes, there are modern-day equivalents of the job of knocker-upper. These include alarm clock companies, phone alarm apps, and wake-up call services. Additionally, some people still employ a personal assistant or family member to physically wake them up in the morning. However, the job of knocker-upper has largely been replaced by technology and is not as common as it once was.