Studies from information-processing and language comprehension research have reported that background knowledge facilitates reading and writing. By comparing Chinese language development of heritage students who had home background in Chinese language and culture with those who did not, this study found that heritage learners did significantly better than their non-heritage counterparts in speaking, listening, grammar, and sentence constructions, but not in reading comprehension, vocabulary learning, and Chinese character writing. These results suggest that heritage learners' oral exposure to their home language does not necessarily lead them to acquire reading and writing skills more quickly than non-heritage learners. Home background knowledge of Chinese, a language with notoriously difficult orthography, may not support reading comprehension or vocabulary learning if that knowledge does not include sufficient exposure to the script system. (Contains 1 table, 2 figures and 1 note.)