Instead of giving flowers for the funeral of their 21-year-old son, they have asked that people give to a charity they have set up in Truett's name.
TobyMac is an American Christian musician who was part of the band DC Talk until 2001 and then made several solo albums.
The eldest of TobyMac's children died unexpectedly last week at their family home in Nashville, Tennessee.
Truett had put out a number of different tracks under different names and had also collaborated with his dad on a number of songs.
On Tuesday, TobyMac shared a photo on Facebook announcing the foundation. The Truett Foster Foundation will raise money to help young people pursue education in music.
"Truett Foster Mckeehan had an untamable grand personality and dreams to match. Since the age of 12, he knew he wanted to make music.
"Dreams are so important to kids growing up. Too many kids do not have the financial ability to pursue their dreams. We want to use this fund to help kids do just that. Get an education, to pursue music, to get the chance to live their dream. Truett would have loved that," the description of the Truett Foster Foundation reads.
According to the foundation's website, donations made in Truett's name will help send "vulnerable youth to college, that they may realize their God-given potential to change the lives of others."
One hundred percent of the donations will be used to fund scholarships in partnership with the Global Orphan Project. The Christian organisation will underwrite all general and administrative expenses in honour of the aspiring musician.
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