There are various visa types for travel to Tibet, for foreign visitors of China orginal but holding a China Q2 visa, we need your China family invitor to provide an invitation letter to prove you are their family members. See sample below:
Visa Type: Q2
Purpose of visit: China Family Visit for visitors of Chinese origin.
>> Passport copy
>> Visa copy
>> A document from your Chinese family member, it must be in Chinese and with invitor's Chinese ID card copies.