Is it permissible to abort a 16-day-old fetus for fear of its impact on another sick daughter who requires special care?

A mother's preoccupation with caring for her sick daughter does not justify aborting a fetus, even if it is only sixteen days old, because this is an act of corruption against progeny without a valid Shar'i (Islamic legal) reason. She must fear Allah and seek His help, for whoever fears Allah — He will make for him a way out.