if your sponsor is not relative to you, you need to request a bank statement to your Bank so they can still know that you are financially capable on your own.
but if you are married or its your immediate family, just photos together is okay, any proof that you really know each other for a long time
no visa needed, Iβm a filipino and Iβm here in Thailand, our immigration in the philippines airport just ask for the hotel accommodation, return ticket and passport. If you are sponsored by others and you will travel alone, you need an Affidavit of Support that can get in a lawfirm office, if the sponsor is with you going to Thailand, no need of that, just a proof that you know each other, just compile all your photos together in your phone π«Άπ»