Bodhisattava
Bodhisattava is an enlightened being who has seen the ultimate truth but is not satisfied to pass into the state of Nirvana because he has promised to help all the animals and human beings until the very last one has been enlightened before passing to Nirvana, according to the Tantra Mahayana Buddhist belief during the 9th-10th century of the Buddhist Era.
The statue you see in the garden is a copy of Bodhisattava Avalokitesavara, aka Kuan Si Im Pho Sak. It is a kind of art that was common during the Song Dynasty in China. Originally, the Bodhisattava images that were influenced from India were male, dressed prestigiously and elegantly like a king. When the Buddhist scripture or Tripitaka was sent to China, it clearly influenced the Chinese art form, which made Chinese Bodhisattavas similar to Indian Bodhisattavas.
Then in the Yuan Dynasty, Chinese Buddhists started to call Phra Nang Maew Zan, the daughter of the King Maew Juang, Phra Kuan Im (Goddess of Mercy) as a result of her goodness, faith, and morality, and her regular practice of religious precepts. When Chinese people immigrated to Thailand, they brought with them the belief in worshiping Phra Kuan Im and a new kind of art form the female Bodhisattavato Thailand as well. So, Kuan Im as you can see in Thailand or in China is female.