Bringing family when you work away from your home coutry so you have a company and family stay together is really important. If you are a work visa holder such as "Engineer/Specilist in Humanities/International Services" and "Skilled Labor" and earn enogh to support the family's finance while living in Japan, the application for the dependent visa is relatively straightforward. However, one must bear in mind that you can only bring "spouse" (i.e. married partner) or "unmarried and under-aged child/children of your own". A problem often arises when you bring your child and who then grows up in Japan. When they finish a secondary education (high school), they are oftern treated as "independent" person therefore they can no longer renew their Dependent Visa. If they go to a college or university in Japan, then they would be granted "Student (留学)" Visa so they can still live in Japan. But what if they wish to start working without going to further education? Work visa such as "Engineer, Specialist in Humanitirs, International Services" (技術・人文知識・国際業務ビザ)requires at least an undergraduate degree or three / ten years of work experience. To save them from this situation, high school leavers may change their status to "Long-Term Resident (定住者)" Visa. For this route, however, the specific condition needs to be met and that is a completion of Japanese compulsory education (elementary and junior high school) prior to being admitted and graduated from high school. Hence it is vital to carefully plan the timing to bring children with working parent to Japan otherwise they may lose a status to stay in Japan when they reach the age of 18 and have to go back to their country where they do not have a foundation to establish a new living .
Please do not give up if your child joined the family in Japan rather late though. If he/she is a high school student in Japan, there is still a chance for them to change the visa to "Designated Activities (特定活動)" upon graduation. Instead of primary and secondary school education in Japan, a high level of Japanese language ability is required (minimum of JLPT N2).
Please note, whichever way, these two visas give the children opportunities to stay in Japan as worker. They have to have secured an employment before applying for the visa. It would be too late to start job hunting when they are about to graduate from high school. Please plan ahead if you have a child who is on Dependent Visa wishing to stay in Japan after finishing high school without going to a further educational institution.