Yes. Bigamy (polygamy) is illegal in every state in the United States. Although Kody is only legally married to Meri (Christine, Janelle, and Robyn married him in religious ceremonies without a legal marriage license), in most states the bigamy law states that 'purporting' to be married or cohabiting with multiple women also counts as Bigamy.
sister wives are not legal anywhere in the united states.
Sister Wives - 2010 Sister Wives Tell All was released on: USA: 22 September 2013
Sister Wives was created on 2010-09-26.
Sister Wives - 2010 Wives on the Move - 1.3 was released on: USA: 3 October 2010
Sister Wives - 2010 Polygamy Questions Answered - 6.7 was released on: USA: September 2013
New episodes of Sister Wives will start airing in May 2013.
Sister Wives - 2010 Mother-in-Law Invasion was released on: USA: 29 December 2013
Sister Wives - 2010 Sister Wives Separated was released on: USA: 13 May 2012
Sister Wives - 2010 Sister Wives Tell All was released on: USA: 22 September 2013
Sister Wives - 2010 Sister Wives on the Strip 2-22 was released on: USA: 20 November 2011
The term co-sister-in-law has no meaning in the English language. A sister-in-law is the sister of one's spouse or the wife of one's brother. In a monogamous society, there is no possibility of a shared, or "co" releationship there. In a polygamous society, perhaps the wives of your brother might be "co-sisters-in-law" but that is pure speculative invention.
Sister Wives was created on 2010-09-26.
Yes, Sister Wives was on the air in 2013.
Sister Wives - 2010 Sister Wives in the City of Sin 2-11 was released on: USA: 5 June 2011
Yes, Sister Wives will be returning.
Sister Wives - 2010 Wives on the Move - 1.3 was released on: USA: 3 October 2010
Your sister-in-laws are your sisters by law after marriage. They are either your spouse's sisters, or the wives of your brothers. Their relatives are not related to you, although some of them will be related to your children.
Your brother's wife is your sister-in-law and your wife is your brother's sister-in-law. The two wives are not related to each other and the English language has no special term for one of them to use in naming the other.