1 Introduction

Due to globalization, immigrant populations growing rapidly and international marriages having become common, the language situation in linguistically mixed families is often complex. Language is an important part of child development. Language skills are invaluable for children to achieve success both in their academics and future career. This may be why more and more parents are drawn to the idea of giving their children the gift of bilingualism and multilingualism (Baker 2000). Although multilingualism has numerous advantages, raising multilingual children is believed to be more complicated than raising their monolingual peers (Shin 2017).

It is well-known that when some languages are learned and maintained at home, others are lost. The language choices negotiated in daily interaction are related to which languages are maintained or lost. Some parents assume that language acquisition is beyond their control, whilst others believe that family language activities can be planned and managed. Grosjean (1982) refers to childhood bilingualism as a conscious decision made by parents; extra efforts, patience, and persistence are generally required to ensure the acquisition and the maintenance of two or more languages.

There are many incentives for children to acquire two or more languages. One common one is that immigrant parents wish their children to acquire both the heritage language (a native, home, or ancestral language) and the societal language (a language commonly used in public life in a society). Immigrant families may employ the policies that favor a heritage language to "enable its members to maintain a connection with their past, strengthen a family bond across generations, and protect through adaptation the integrity of the family in response to external forces" (Tannenbaum 2012: 62). In this instance the home environment and parents are the best and often the only sources for transmitting the heritage language and culture to the younger generation which, otherwise, would be deemed to be lost (Fishman 1991).

How parents perceive different languages and how they negotiate the use of the totality of their linguistic repertoires directly affect their children's acquisition of each of these languages. Making decisions is especially necessary when children are involved in a family where each parent speaks a different native language (King and Fogle 2006). Thus, the linguistic characteristics of multilingual families have aroused a keen interest in the growing field of family language policy (FLP) (King, Fogle, and Logan-Terry 2008).

1.1 A study of the trilingual child, Y

I became interested in the topic of family language policy because I am part of a multilingual family, being a Chinese married to a Japanese. I met my husband in Scotland and we spoke only in English with each other in this foreign land. In addition to the fact that we were in an English-speaking country, neither of us spoke the other's native language, so English was the natural default language. When we started to live together as a family in Japan, I was granted many opportunities to learn Japanese and become trilingual. Although we continued to share our thoughts and hobbies using English in Japan, for the first time, we felt a need to establish a language policy (LP) among ourselves if we were to continue speaking the language that we used with each other in the place where we first met. This desire became even stronger when our daughter, Y, was born. We often discussed and argued about what kind of language policies would be best for her and for the whole family. In the meanwhile, I decided to go back to graduate school and research multilingual child development and family language policy.

This book is an extension of the study done for my doctoral dissertation, which was an ethnographic1 case study of the trilingual development of Y from birth until the age of 5;10 (5 years; 10 months). I have now followed her development for eight years. We do not live very close to any of our extended family members and therefore I, my husband, and Y are always the main participants in the study. Y's Chinese grandparents visited Japan and lived together with us for about three months when she was two years old (2;6-2;9). This is the only occasion when outside participants were closely involved in this study.

Although the original focus of the doctoral research was family language policy, as Y developed, she exerted unexpected influence on our family's policies. For example, she expressed a desire to acquire Chinese language, culture, and identity, including the reading and writing of Chinese characters, when she was two years old, though my previous expectation was only for her to be able to make daily conversations in Mandarin. In addition, Y picked up International Phonetic Alphabet (IPA) at age four as she looked up words in a dictionary. She also memorized the lyrics of one version of Disney's Frozen song - "Let it Go" (a song sung by 25 singers in 25 languages)2 as a five-year-old. This achievement gave her a lot of motivation to add Spanish to her trilingualism. What Y had done had gone far beyond my imagination and this led me to become increasingly aware of child agency.3

Y reads and writes above grade level in English and Japanese at the present time. She has been reading Penguin Classics (e.g. A Tale of Two Cities4) and Oxford School Shakespeare: Romeo and Juliet5 since she was six years old. Her favorite authors include William Shakespeare, Jane Austin, Victor Hugo, Charles Dickens, Louisa May Alcott, and Conan Doyle. In addition to classic novels, she is keen on reading about world history, particularly English, Scottish, and French history. Y also reads extensively in Japanese. She could read both fiction and non-fiction books listed for Primary 5 students and above when she was only in Primary 1. Some of the fiction and history books that she reads in Japanese overlap with the contents that she reads in English. She is critical about the facts that are retold in Japanese if they originate from English. She also started to read Japanese newspapers designed for primary and secondary school students every day from six years old. As for Mandarin, she enjoys learning from the Mandarin textbooks that are widely used in primary schools in China. She also loves Chinese storybooks and classic novels, particularly a well-known one called Three Kingdoms.

Y began to learn Spanish on her own at six. She has done this by using Spanish language textbooks for adult beginners, listening to the books' audio recordings, and watching their online lessons. She also reads bilingual stories written in English and Spanish and memorizes the lyrics of Spanish songs. Furthermore, she started to learn Japanese sign language from seven years old. She reads newspaper articles and books introducing this language. She also teaches the language to her parents, uses it in daily conversations (e.g. using one of her three languages and Japanese sign language at the same time when singing or talking), and makes storybooks about it at home. Her teacher reported that Y created a sign language corner in the classroom and encouraged her peers to make sign language booklets and posters together with her. Y's suggestion of using Japanese sign language together with the Japanese spoken language in routine greetings (e.g. formulaic phrases said before starting a lesson and eating school lunch) was also adopted by her teacher and classmates.

In addition to reading in her three main languages, Y also enjoys writing creatively in all of the three. She has developed writing as a hobby and a habit from four, thinking of herself as an "author" and producing at least one piece of writing every day. She published two essays and three poems in the first and second grades in a Japanese daily newspaper called Mainichi Shougakusei Shinbun [Daily Primary School Newspaper].6 I was surprised to find that Y was categorizing her work into six main types and that she had prepared six notebooks, one for each type of writing: fairy tales, chapter books, poems, Y's diary, general essays, and argumentative essays. I noticed some of these notebooks when she was four and gradually found the others after she turned five.

What surprised me more was that she started to read my research diary and check the mistakes in my notes (from age three). For example, she would correct the name of a book that she had read which I had referred to, or the words that she said in a conversation. She also kept a field journal occasionally, recording her own activities and observation on her classmates' learning (from age five). Moreover, she was "proofreading" my doctoral dissertation and book manuscript in its various stages (from age four). Y's support for my research has thus been both multilingual and multimodal. In the course of the study, she developed from an infant participant to a child ethnographer, studying herself and the data on herself.

Although I myself do not feel that I have done anything exceptional or that my daughter is particularly exceptional, many people have remarked at how exceptional she is and suggested that she might be called a gifted child. I admit that Y's achievements deserve loud applause; however, what I...