"(Love Is) Thicker Than Water" is a song performed by Andy Gibb, released in 1977, it was his second single that topped the US Billboard Hot 100. It was mainly written by Barry Gibb, with help from Andy Gibb. The B-side of this song was "Words and Music" in the US, but "Flowing Rivers" in the UK. It became a gold record.

Billboard magazine describes the song as "a midtempo ballad that changes pace from a lushly romantic and soft [Andy] Gibb vocal to an uptempo instrumental drive. Plenty of melody and another catchy hook".

"(Love Is) Thicker Than Water" was written originally by Barry Gibb in Bermuda alone with Andy Gibb credited as co-writer on the latter. Andy Gibb later revealed writing a song with Barry:

"(Love Is) Thicker than Water" was recorded in October 1976 at the Criteria Studios in Miami, Florida, during the same time as "I Just Want to Be Your Everything". On the two tracks, Joe Walsh of Eagles played guitar. The song was certified Gold in the United States on 16 February 1978 as Robert Stigwood presented Gibb with his first gold record at the Roxy in Los Angeles.

As evidence of the Gibb brothers' U.S. chart domination in 1978, atop the 4 March 1978 Hot 100 the Bee Gees' "Stayin' Alive" was displaced by this song, which in turn was displaced two weeks later by the Bee Gees' "Night Fever", which in turn was displaced eight weeks later by Yvonne Elliman's "If I Can't Have You". Since Barry Gibb had a hand in writing all four of these songs, he became the only person in history to write four consecutive US number-one singles, a feat unmatched to this day. The song was released in February 1978 in Netherlands.

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