Question: What do Markus Feehily and Ian Gillan have in common?

Context paragraphs:
Markus Feehily: Markus Michael Patrick Feehily (formerly known as Mark Feehily, born 28 May 1980) is an Irish singer and songwriter.  He was one of the lead singers of the boy band Westlife from 1998 to 2012.

Gillan's Inn: Gillan's Inn is an album by Ian Gillan in celebration of his 40 years as a singer.  The first release was a DualDisc composed of both a CD and a DVD side.  The CD featured re-recorded tracks from all eras of Ian Gillan's singing career.  In a recent interview Gillan observed that, despite the number of participants and guest appearances, this was the easiest project he ever put together.

The Javelins: The Javelins, sometimes also known as Ian Gillan & the Javelins, was a 1960s band fronted by Ian Gillan of Deep Purple.  The band played live but never recorded in their initial spell together.  The other members included rhythm guitarist Tony Tacon, bass player Tony Whitfield,drummer Keith Roach and lead guitarist Gordon Fairminer.  All from Hayes/Heston area of West London.

Ian Gillan: Ian Gillan (born 19 August 1945) is an English singer and songwriter.  He originally found commercial success as the lead singer and lyricist for Deep Purple.

Joe Mennonna: Joe Mennonna is an accomplished session musician who worked with Ian Gillan and Roger Glover on their 1988 album "Accidentally on Purpose", and toured with Ian Gillan in September 2006 in support of the "Gillan's Inn" album.  He also appears on Gillan's "Live in Anaheim".

Fire (Markus Feehily album): Fire is the debut solo studio album by Irish singer-songwriter and former Westlife vocalist Markus Feehily.  The album was released on October 16, 2015, via Harmoney Entertainment, as part of the Kobalt Music Group.  The album includes the singles "Love is a Drug" and "Butterfly".

Love Is a Drug (Markus Feehily song): "Love Is a Drug" is a song by Irish singer and songwriter and former member of Westlife Markus Feehily.  The song was released in the United Kingdom as a digital download On 19 April 2015 through Harmoney Entertainment.  It was released as the lead single from his debut studio album "Fire" (2015).  The song was written by Markus Feehily, Steve Anderson and Tinashé Fazakerley; and produced by Mojam.  The song has peaked at number 65 on the Irish Singles Chart and number 55 on the UK Singles Chart.

Naked Thunder: Naked Thunder is a 1990 solo album by Ian Gillan, released soon after his departure from Deep Purple in 1989.  It features a varied selection of songs, with one of Gillan's most passionate and impressive performances on power ballad "Loving on Borrowed Time" and traditional field lament "No More Cane on the Brazos".  It was also the first album to feature Ian Gillan's long time writing partner Steve Morris.  "Naked Thunder" was produced by Leif Mases and features a number of notable guest musicians, including drummer Simon Phillips and former Grease Band keyboard player Tommy Eyre.

Lily Elise: Lily Elise (born February 20, 1991) is a singer, songwriter from Berkeley, California.  Elise has worked with artists such as Dillon Francis, Twin Shadow, Felix Cartal, Audra Mae, Gigi Radics, Markus Feehily and Hayden Panettiere.  On November 4, 2014, she released the lead single "Generator," from her debut EP "Taken".

Toolbox (album): Toolbox is the second solo album by Ian Gillan originally released only in Europe, Japan and Brazil on German label EastWest.  It was Gillan's last album before his second comeback with Deep Purple in August 1992.  The subsequent mammoth 10-month tour, which crossed Europe and South America, proved Ian Gillan to be a strong live attraction.  Although "Toolbox" wasn't a big commercial success it is considered by many as one of Gillan's finest records.  The album was finally released domestically in the USA in 1997.

Supporting paragraphs: Markus Feehily Ian Gillan
Answer: singer and songwriter