https://bbs.gter.net/viewthread.php?tid=1323623&highlight=
If you are not the personholding the financial standing, you will also need to provide a statement whichcan prove the relationship of your sponsor and you. Such proof can be the birthcertificate or household registration if your sponsor is your parent, or aletter / statement signed by your sponsor who is your relative orfriend. (如有關資產證明不屬於申請人,請另提交關係證明。如資助人是申請人的父母,請提交出生證明文件或戶籍證明;如資助人是親戚或朋友,須提交該資助人署名的信件一份,證明該位人士願意資助申請人來港就讀本系碩士課程。)
https://bbs.gter.net/thread-1080586-1-3.html
If your parents will support your studies, please submit (i) their bank statements, saving account passbooks or salary proof; (ii) proof of relationship between you and your parents (e.g. birth certificate and their marriage certificate, or 公证书 (for mainland applicants)); (iii) a letter stating that they will support you financially. The letter must be signed by them.