Kung aagawin mo ang lahat sa akin (1987)

An intense sibling rivalry has always existed between Gladys Andrada (Jackie Lou Blanco) and her older sister Maureen (Sharon Cuneta), whom her parents had adopted before she was born. Their father Gilbert Andrada (Dante Rivero) treats them fairly and loves them unconditionally, but their mother Clara (Laurice Guillen) does not. As a result, Gladys has grown up a scheming, selfish, egocentric brat who always wants to have her own way and get everything she wants--now including the man Maureen has learned to love.