Despite all the ups and downs, 2017 has been a year to savour for Moriya and Ariya Jutanugarn for many reasons.
Ariya, who became the first Thai golfer in history to reach the top of the sport in June, said: "2017 is my favourite year so far, not because I hit the peak of my career or because I was able to win championships, but because it was full of challenges.
"I saw the best and worst of me as a player, learned a lot from it and then gained more confidence."
Ariya won her second victory of 2017 at the season-ending Tour Championship last month.
Meanwhile, elder sister Moriya also made quite an accomplishment by finishing in the top 10 in 11 tournaments this year.
Moriya said: "What achieved this year was wonderful, and I hope to keep improving. I will keep pursuing my first LPGA title next year."
Moriya and Ariya, who are currently enjoying a break in Thailand, will soon fly to the United States to prepare for the Pure Silk-Bahamas LPGA Classic next month.
They will later return to Thailand to compete in the Honda LPGA Thailand from Feb 22-25 at Siam Country Club in Pattaya.
Moriya added that she was always happy to participate in the event, saying: "We only play in Thailand once a year, so of course there is excitement. We will practise hard for the tournament."
Ariya said: "We grew up playing in the Honda LPGA Thailand and it is the event I most cherish. The line-up at the tournament has always been quite spectacular so I am very keen to impress everyone at the event."