Carl XVI Gustav and Silva currently hold the titles of king and queen, respectively. During their union, these Swedish royals welcomed three children into the fold. — two daughters and a son. Initially, second-born Prince Carl Filipe was set to become the country's next king; however, succession laws changed in 1980 and decreed that the king's firstborn child would rule after him, regardless of gender. The changes meant Prince Carl Filipe was no longer next in line and instead, the eldest daughter of the king and queen, Princess Victoria, would inherit the crown. When this time arrives, Victoria will take her place as Sweden's first queen regnant since the 1700s (via People).
When Princess Victoria takes the throne and her husband, Prince Daniel, becomes king, their oldest child, Princess Estelle, will become the heir apparent. Had the succession laws not changed in the 1980s, Prince Oscar would've become the heir apparent.
In 2019, Estelle and Oscar's cousins — the children of Prince Filipe and Princess Sofia, and Princess Madeline and Christopher O'Neill — were stripped of the title "royal highness" and official royal duties, according to BBC News. Nevertheless, all of the royal grandchildren remain beloved family members and will retain their titles of dukes and duchesses, but they are not tied to the crown as Princess Estelle and Prince Oscar are.