Device finished... batteries charged and it should last for billions of uses with the supernatural amount of efficiency Jeff was able to pack into it. Most scientists would be surprised that he was able to do that in his parent's garage with relatively crude implements. His father was a mechanic so it wasn't like he was starved for tools, but they were far from precision tools needed for most computer hardware. All that wasn't too important though as Jeff had made the transformation remote, and he walked out of the garage and into the living room. Their father were off at work, and their mother may have been just a room away but... I mean this was just going to be a prank and he'd be found out quickly anyways.
Megan was laying on a couch and looking at her phone. The 14 year old could be so bitchy and demanding like a baby always crying for something. Jeff set the transformation remote to set the age of the target to 1 year old and fired. The remote fired a beam which hit Megan directly, and soon Jeff saw her little sister become his baby sister swimming in her clothes unsure what was going on and started crying.
Jeff smirked and was about to reveal himself and his invention, but then the remote started to seem to spark causing him to drop the remote. At the same time their mother came into the room unsure what was going on when the remote hit the hard ground causing a failure in the remote to grow further as the trigger and energy supply went haywire. The beam widening and going through everything in the entire world. For some reason the error only affected human females, but that was enough for sheer chaos to occur.
Jeff only got a taste of the oddity as in his home significantly away from any traffic he only noticed his mother shrinking into a baby as well. Concerned he grabbed his baby mom and paired her with his sister on the couch as he tried to explain the situation to them. He didn't think he could leave them alone, but he also couldn't fix his remote while looking over two babies. After all babies couldn't do a whole lot and were pretty vulnerable...
*meanwhile in the outside world* about half the cars currently driving found themselves piloted by infants, and massive traffic incidents occurred worldwide. In general roughly half the world turning into infants caused many issues for everyone around them. Aside from death via women operating things that could easily kill someone if used improperly there was death by pregnancy for many women pregnant with male fetus'. The female fetus' ended up aging to 1 years old as well which usually happened before the woman got too small to give birth properly, but unless the pregnancy was really early a 1 year old female bodies weren't designed to hold several month old fetus' in their wombs. Governments and a lot of companies in general were having issues as key leaders and workers were all rendered incapable of doing their jobs. Let's just say there was a lot of pandemonium in the coming days.
The remote pulse was easily tracked and Jeff was sent to jail for the time being leaving his father to take care of two babies alone in a world of massive uncertainty and economic collapse. Jeff himself was trying to explain what happened and was begging to get to the remote, but everyone viewed him as some psychopathic mad scientist. The top scientists who were still around couldn't make heads or tails of the remains of the transformation remote. This left the American government to ponder whether they let Jeff have a chance to make everything better? Whether they should leave the scientists to figure it all out eventually... or be shady and figure out all the ways to profit off this incident.