@Sophie ************
yeah it what I was thinking but says for dv3 -child under 20 visa:
1. Bio data page of passport
2. Photograph past 6 months
3. Document indicating current location
4. Financial evidence: amount no less than £11,000 (500,000 THB) e.g bank statement, sponsorship letter
5. DTV visa of DTV holder
6. Proof of relationship to DTV holder
Extras:
Passport of parent
Parents council tax bill utility bill
Parents recent official bank statement show name and address
So wondering if now looking that I can do just a sponsorship letter