30 Rock star John Lutz has announced the shock death of his younger brother in a heartbreaking post.

Lutz, aged 52 and recognized for his role as J. D. Lutz on the NBC series, expressed being ‘heartbroken’ over his brother’s unexpected death on Thursday. Joel leaves behind a wife and four young kids.

Joel, believed to be approximately 50 years old, served as the Executive Director of mosaiXmultiply, an organization dedicated to establishing hundreds of multicultural churches globally.

Lutz wrote: ‘My younger brother Joel passed away suddenly this past Thursday. My family and I are heartbroken. 

‘He was a humorous, caring, and affectionate person. There are countless other things I wish to share about him, but at this moment, I’m too devastated to continue writing. I love you, Joel.

He shared another post linking to a GoFundMe for Joel’s family – wife Jenni, twins Ellery and Rhea, 15, Zoe, 13 and Josiah, 10. 

30 Rock star John Lutz has announced the shock death of his younger brother Joel in a heartbreaking post

Lutz, 52, who is best known for playing J. D. Lutz on the NBC sitcom, said he was ‘heartbroken’ over his brother’s ‘sudden’ passing on Thursday, leaving behind a wife and four young children

The fundraiser has generated more than $60,000. 

A tribute on Joel’s company website confirmed he died from ‘natural causes’ and read: ‘Joel was more than our leader – he was a loving husband & father, a visionary, a mentor, a friend, and a faithful follower of Jesus. 

‘Joel inspired everybody who worked in mosaiXmultiply with his vision and ability to motivate. With his ability to bring leaders in various countries into the mXm community and mobilize them with a vision for movement. 

‘He created a solid foundation for mXm’s purpose of globally training and mobilizing common people to plant gospel communities where they live that are missional, multicultural and multiplying. His unwavering dedication to the mission and his deep love for people have left a lasting mark on all of us.

‘We take comfort in knowing that Joel is now with our Savior praising Him with brothers and sisters from every culture. 

‘Please keep his family, friends, and the entire mosaiXmultiply community in your prayers as we navigate this season of sorrow and remembrance.’

Per his company bio, Joel and his wife Jenni joined a startup team for a ‘Christ-centered community’ in Frankfurt, Germany.

Joel also served as a pastoral advisor in Wake Forest, North Carolina.

He shared another post linking to a GoFundMe for Joel’s family – wife Jenni, twins Ellery and Rhea, 15, Zoe, 13 and Josiah, 10

Joel, who was believed to be around 50, worked as the Executive Director of mosaiXmultiply, an organization helping to plant hundreds of multi-cultural churches around the world

Lutz wrote: ‘My younger brother Joel passed away suddenly this past Thursday. My family and I are heartbroken’

Actor and comedian Lutz joined 30 Rock in its fourth season in 2009, playing a lazy, overweight writer who is often insulted or made fun of by the rest of the staff.

He was also a writer on Saturday Night Live for seven seasons.

In 2014, he joined the writing staff of the NBC late-night talk show Late Night with Seth Meyers