"... despite the inevitable warm fuzziness brought on by something as cute as a baby chimp, Half Brother turns out not to be your usual animal book. Oppel is rarely far away from reminding us that chimps are powerful creatures, often destructive, occasionally murderous." "Oppel is pleasingly unafraid to ask awkward questions, often right at the point where readers might have made up their minds. What a particular joy for a teenage reader, to be challenged rather than instructed. Parents might be surprised at the passionate discussions Half Brother ends up inspiring, along with a healthy new respect for our closest genetic cousins."