Complex sentence: In the Japanese autumn of 1987, having met a new boyfriend, the mother placed Child A in charge of the others, leaving him with ¥50,000 (a little over US $500) for their living expenses alone in their Tokyo apartment.
Split into simpler sentences: In the Japanese autumn of 1987, having met a new boyfriend, the mother placed Child A in charge of the others and. Leaving him with ¥50,000 (a little over US $500) for their living expenses alone in their Tokyo apartment.