Andy Grammer to Honor His Late Mother in 'Dancing With the Stars' Performance (Exclusive Video)

In what is sure to be one of the most emotional shows of the season on Dancing With The Stars, Andy Grammer will honor the memory of his mother for week four’s theme of "My Most Memorable Year."

Grammer — who will dance the cha-cha to his new single, "Good to be Alive" — chose the year of 2009 as not only his most memorable year, but his most heartbreaking as the singer lost his mother to breast cancer. The show will air Monday night (Oct. 5).

As seen in this Hollywood Reporter exclusive, Grammer shares how he started the year busking at Santa Monica's Third Street Promenade as "a street performer paying my rent, driving my mom’s minivan. My guitar case would be open and I’d pretty much go out there for eight hours a day."

The 31-year old Los Angeles native was driving to a performance at a camp when he received a call that his mom had breast cancer. Even worse — it was caught "really late" and he only had "two or three days to say goodbye."

Devastated, the musician walked "dazed and confused" around Los Angeles until one day out of desperation he wrote a "pick me up" song called "Keep Your Head Up."

"The song that I wrote from it was what started my whole career," he said.

Ten couples compete tonight on DWTS, airing 8 p.m. on ABC.