Older brother of the late singer Christina Grimmie who tackled his sister's killer the night that she tragically lost her life after an Orlando concert. Mark is a musician and music producer himself.
He was previously a music producer for Selena Gomez.
He was his sister's tour manager and often played guitar alongside the singer.
He was born to parents Tina and Albert.
His sister Christina was a contestant on The Voice. Friends she made from the series, like Adam Levine, shared their sentiments on social media following the tragic incident.