SANTA BARBARA, Calif. -

Classmates took part in a memorial at La Colina Junior High after school Friday.

They are mourning Sebastian and Vincent Holzer.  Their father is accused of stabbing them to death in their Goleta home on August 11.  Their grandparents and their Australian shepherd Dixie were fatally stabbed too.

Sebastian died the day after his 13th birthday. He would have been an eighth grader at La Colina. His principal said healing will be slow and painful but that his classmates should have hope.

Associated Student Body president Michelle Qin read from a letter Sebastian wrote to a friend  at the beginning of the school year last year. His advice was never to procrastinate or do the minimum.

His teachers said he was curious about everything. He liked to fish on East Beach in Santa Barbara and he like to wear the Lions school colors: green and gold.

His little brother Vincent was 10 and owuld have been a fifth grader at Foothill Elementary School.

Their grandmother was remembered for taking an interest in their education.

Sebastian's best friend, Connor Kelly, said he played Minecraft with Sebastian every night including the day of the slaying.  Kelly said he made a Minecraft tribute.

Students have covered a fence on campus with photos and messages. Many of them said the brothers will be missed and remembered.

Kelly hopes to plant a tree in their memory too.