NEW : President Obama praises Thomas ' work . Thomas died of pancreatic cancer on Halloween . He was 15 when he and others visited their schools in 1957 . He was a Christian who sincerely promoted racial harmony and took his responsibilities seriously . '' Other Little Rock community members remember Thomas as being able to keep them laughing .
NEW : President Obama praises Thomas ' work . Thomas died of pancreatic cancer on Halloween . He was 15 when he and others visited their schools in 1957 . Other Little Rock community members remember Thomas as being able to keep them laughing .