Complex sentence: Justine Dufour-Lapointe won the first gold medal in freestyle skiing (women's moguls) and her sister, Chloé Dufour-Lapointe, finished in second place in the same event, earning the country's first silver medal.
Split into simpler sentences: Justine Dufour-Lapointe won the first gold medal in the freestyle skiing (women's moguls) event. Justine's sister, Chloé Dufour-Lapointe, competed in the same event and finished in second place, earning the first silver medal.