Siouan languages
In the 19th century, Robert Latham suggested that the Siouan languages are related to the Caddoan and Iroquoian languages. In 1931, Louis Allen presented the first list of systematic correspondences between a set of 25 lexical items in Siouan and Iroquoian. In the 1960s and 1970s, Wallace Chafe further explored the link between Siouan and Caddoan languages. In the 1990s, Marianne Mithun compared the morphology and syntax of all the three families. At present, this Macro-Siouan hypothesis is not considered proved, and the similarities between the three families may instead be due to their protolanguages having been part of a sprachbund.
Laomian language
Laomian (also known as Bisu, Guba or Lawmeh) is a Sino-Tibetan language and is a Chinese derivation of the Lahu name Lawmeh. Laomian is closely related to the Bisu language, is spoken in Laomian Dazhai 老缅大寨, Zhutang Township 竹塘乡, Lancang County, Yunnan. There are 4,000 speakers (out of 5,000 ethnic members) in central Lancang County, Yunnan (Bradley 2007), and fewer than 1,000 Laopin speakers, which may not be included in these numbers. It's language family consists of Sino-Tibetan, Tibeto-Burman, Ngwi-Burmese, Ngwi, Southern, Bisoid, Bisu-Pyen-Laomian, Bisu, Pyen, and Laomian. It is mostly spoken in China in the Southwestern areas of Yunnan Province that joins Thailand and Myanmar. Speakers of Laomian that live in areas with different ethnic groups mostly speak Laomian in their home, while using the main local ethnic language in public. The average age of Laomian speakers is increasing into the sixties to seventies in areas of heterogeneous communities because children are learning the main local language. The domination of Chinese language has had a major impact on the villages of the Laomian people due to the increasing number of people who can speak multiple languages.