You arrived at your dad's place, pulling your car up into the usual spot. You popped in through the backdoor, and just as you had suspected, your dad was busy remodeling the living room (hence why no front door access). You took a seat and waited a minute for your dad to turn off the saw and notice your presence.
"Oh! Hey kiddo, what's up?" He said, turning around and getting right back to his toolbox.
You keep the Age Device tucked out of sight and reply,
"Just bored after work. Think I could give you a hand?"
"Sure!" Your dad replied, beaming with enthusiasm to have someone to work with.
As soon as he turns around, however, you set the Age Device to physical, mental, reality and clothes, and press the backwards button dozens of times before standing up and getting your gloves on.
You hold a beam in place for him while he installs a series of screws, but he starts to get a bit distracted as he does so. His wrinkles start to clear up, his hair becomes colored... and then it grows back in the middle. He went from his early 60's to his mid 30's--only a few years older than you.
A half hour of DIY'ing goes by until you both take a break for coffee. You wait for an opportune moment of his back being turned, and afflict him with several more presses of the Age Device. By the time you're both back on the task, your dad is in his early 20's. So much leaner, lighter skinned and thicker-haired. You wait for him to direct you to the next beam, but soon realize from his body language that he is waiting for your orders on what to do next. I guess that makes sense, you have the seniority on this project now. Another half hour goes by, under your direction. You don't do as good a job as your dad would have, but considering he only has a few years of professional experience now thanks to the regression, you're the best qualified at this point.
You tell him to get the wrench on the mantle, and watch him diligently follow your instruction. You take advantage of his back being turned again, and use the device to regress him further. By the time he has turned back and handed you the wrench, he is in his adolescence. You guide him back over to the next beam to install, and watch as he continues to age back as you put in screws. His body hair thins, his face becomes smaller, his muscles reduce in size significantly and he shrinks about five inches; left now at the age of 14. You no longer let him keep seriously working with you; now he's just handing you tools and holding things up for you. You're teach him how to handle tools, how to measure and cut...all things that your dad himself taught you, but which has now departed his understanding, and which he is now dependent on you to teach him.