Question: On Big Brother 18 a host returned who worked for CBS. She was a co-anchor on what?

Context paragraphs:
Celebrity Big Brother 8 (UK): Celebrity Big Brother 2011, also known as Celebrity Big Brother 8, was the eighth series of the British reality television series "Celebrity Big Brother".  It was the first series of "Celebrity Big Brother" to air on Channel 5, and the first celebrity series not to air in January since "Celebrity Big Brother 2", which was broadcast in November 2002.  The series launched on 18 August 2011, and ended after 22 days on 8 September 2011, making it the shortest Channel 5 series.  It was followed by the twelfth regular series, which launched the following night after the final.  Davina McCall did not return to host the main show, and was replaced by former winner Brian Dowling.  Emma Willis presented the spin-off show "Big Brother's Bit on the Side", alongside Jamie East and Alice Levine.  Marcus Bentley returned as commentator for the live shows and highlights whilst also providing voice over for viewer competitions.

Big Brother: Over the Top: Big Brother: Over the Top (or BBOTT for short) is a spin-off American reality television series of the show "Big Brother" that aired exclusively online.  The season premiered on September 28, 2016 and ended after 65 days with a season finale on December 1, 2016 only on CBS All Access, an over-the-top subscription streaming service.  The season was officially announced by CBS on August 3, 2016, while "Big Brother 18" was still in progress.

Celebrity Big Brother 6 (UK): Celebrity Big Brother 2009, also known as Celebrity Big Brother 6, was the sixth series of "Celebrity Big Brother".  It was broadcast on Channel 4, launching on 2 January 2009 and running for 22 days until 23 January 2009.  The launch show was watched by approximately 6.4 million people.  Davina McCall returned as main presenter, with George Lamb as host of "Big Brother's Little Brother", and Jack Whitehall as host of "Big Brother's Big Mouth".  The winner of this series was Ulrika Jonsson, with Terry Christian second.

List of Big Brother: Over the Top houseguests: Twelve new contestants for "" were revealed on September 26, 2016.  For days following the Big Brother 18 finale, viewers were given the opportunity to vote between two previous over-the-top "Big Brother" contestants as the thirteenth houseguest - Jason Roy from "Big Brother 17" and Jozea Flores from "Big Brother 18".  On move-in night, it was revealed that Roy won the public vote and entered the Over the Top house.

Big Brother 16 (UK): Big Brother 2015, also known as Big Brother 16 and Big Brother: Timebomb, was the sixteenth series of the British reality television series "Big Brother", hosted by Emma Willis and narrated by Marcus Bentley.  The series launched on Channel 5 in the United Kingdom and TV3 in the Republic of Ireland on 12 May 2015 and ended on 16 July 2015, a week earlier than planned.  This was the earliest launch of a "Big Brother" series since the show's inception in 2000.  It is the fifth regular series and the thirteenth series of "Big Brother" overall to air on Channel 5, and is the first regular series to air in May since "Big Brother 8" in 2007.  It is also the first series to air in Ireland since its move to Channel 5 in 2011.  On 2 February 2015, it was revealed that Willis had stepped down as a host on the show's spin-off series "Big Brother's Bit on the Side", though Rylan Clark will continue.

Celebrity Big Brother 18 (UK): Celebrity Big Brother 18 was the eighteenth series of the British reality television series "Celebrity Big Brother", hosted by Emma Willis and narrated by Marcus Bentley.  The series launched on 28 July 2016, just two days after the conclusion of "Big Brother 17" on Channel 5 in the United Kingdom and TV3 in Ireland.  The series ended on 26 August 2016, making it the longest summer series to date and the third-longest series of "Celebrity Big Brother" in its history, behind series 15 and 17, respectively.  Rylan Clark-Neal continues to present the spin-off show "Celebrity Big Brother's Bit on the Side".  It is the eleventh celebrity series and the seventeenth series of "Big Brother" overall to air on Channel 5.

Big Brother 18 (U.S.): Big Brother 18 is the eighteenth season of the American reality television series "Big Brother."  The season premiered on June 22, 2016 on CBS with a two-hour season premiere and ended with a 90-minute season finale on September 21, 2016.  Julie Chen returned as host.  On September 21, 2016, Nicole Franzel won the game in a 5-4 vote against Paul Abrahamian.  The season lasted for 99 days making it the longest running season in the show's 16-year history.

Big Brother 18 (UK): Big Brother 2017, also known as Big Brother 18 and The United Kingdom of Big Brother, was the eighteenth series of the British reality television series "Big Brother", hosted by Emma Willis and narrated by Marcus Bentley.  The series launched on 5 June 2017 on Channel 5, and ended after 54 days on 28 July 2017.  Rylan Clark-Neal continues to present the spin-off show "Big Brother's Bit on the Side".  The series, along with its spin-off, continues to air on 3e in Ireland, as part of a three-year deal between the Irish broadcaster and Endemol Shine Group.  It is the seventh regular series and the nineteenth series of "Big Brother" in total to air on Channel 5 to date.

Julie Chen: Julie Suzanne Chen (born January 6, 1970) is an American television personality, news anchor, and producer for CBS.  She has been the host of the U.S. version of the CBS reality-television program "Big Brother" since its debut in July 2000 and is the longest-serving host of any country's version of the show.  She is also a co-host and the moderator of the CBS daytime show "The Talk".  Previously, she was a co-anchor of "The Early Show" on CBS.

Celebrity Big Brother 13 (UK): Celebrity Big Brother 13 was the thirteenth series of the British reality television series "Celebrity Big Brother".  The series launched on 3 January 2014 on Channel 5 and was originally meant to end after 22 days on 24 January 2014.  However, it was extended due to ratings success and instead ended after 27 days on 29 January 2014, making it the longest Channel 5 series of the show (at the time, since beaten by "Celebrity Big Brother 15") and the joint-longest series, along with "Celebrity Big Brother 7" in 2010.  It is the sixth celebrity series and the ninth series of "Big Brother" overall to air on the channel.  Emma Willis returned to host the series, whilst Rylan Clark returned to present spin-off show "Big Brother's Bit on the Side" along with Willis.

Supporting paragraphs: Big Brother 18 (U.S.) Julie Chen
Answer: The Early Show