Orthographic knowledge is predicted to be central in the process of children’s reading development. We examined both the temporal order between orthographic knowledge and each of word reading and word spelling—effectively, which predicts which by including autoregressive controls— and cross-linguistic transfer between English and French for our emerging bilingual participants. Seven-three children (36 males) were followed from Grades 1 to 3 in a French immersion program in which instruction was entirely in French. We conducted cross-lagged panel models of orthographic knowledge, word reading, and spelling that included controls of phonological awareness, non-verbal ability. In terms of temporal order, word reading (at grade 1) and word spelling (at grade 2) predicted gains in each of English and French orthographic knowledge. In contrast, early orthographic knowledge did not predict gains in word reading or word spelling in either language. In terms of transfer, from their earliest point of measurement, English word reading and spelling consistently predicted later French orthographic knowledge; French word reading and spelling contributed to English orthographic knowledge only from Grade 2. These findings illustrate a dynamic picture of the relations between orthographic knowledge and word reading and spelling both within and across languages, informing current models of each reading with both monolinguals and bilinguals.