Frankly speaking, Lao doesn't need Isan and Lanna come back to Laos and also Isan and Lanna don't need to be Lao too. Present day there are only Laos and Thailand, there is no Lao right or Lao left either Red Lao or White Lao. Only people who name themself Lao Nok prefer to say Isan and Lanna are Laos, no more Lao territory except Lao PDR land. If you still insist Isan and Lanna are Lao, Please ask them that they also need to be Lao? Please do not stay with the past, wake up man.
I rain into Ananda at restaurent in Bangkok Thailand, and I had about ten minutes conversation with him. He said he was in his mother stomach when his father went to bring his mom from Laos to Thailand. He born in Thailand 6 months after his mom got to Bangkok. He's 100% Thai citizen, he's not Lao nor Australian. He knew that his mom is Laotian when he was 18 years old, he knew only his father is Australian since he was kid but not his mom.