Princess Bubblegum has made her biggest achievement yet, a Time Machine! With Marceline as the test subject, she sets the machine to 1000 years back, only for it to malfunction and instead send Marceline's AGE 1000 years back. Trusting Marceline's safety with Finn, she returns to research. But the main question is "How is a 15 year old going to take care of a baby?" [First Story]