This article focuses on the effect of home educational activities on the first language (L1) English development of two bilingual children. Their development is approached from a usage-based and a dynamic systems perspective, investigating both the relationship between input and production, and the individual learning trajectories of both children. The article heeds recent calls to investigate the development of verb-argument-constructions (VACs) longitudinally in individual learners. Two simultaneous bilingual children, learning English and Mandarin as L1s and aged 3;8.28 and 3;7.15 at the start of the investigation, were recorded every two-three weeks for about one year while taking part in home educational activities such as shared-book reading. All verbs and their frequencies used in verb-direct object VACs in input and production were extracted and their development investigated. Results confirm both usage-based and dynamic assumptions on language learning. In line with usage-based assumptions, both input and production VAC verb frequencies were Zipfian, each child followed their own input more closely than the other child's input, and production began with using the more frequent verbs before diversification. In line with dynamic assumptions, the children show individual differences in the variability of VAC verb use and the amount of verb diversification, with the more proficient child (as measured at pre-test) exhibiting higher variability and diversification. This underscores the complementary nature of group and individual studies and attests to the importance of the shape of the input for individual development. Moreover, it shows that development is individually owned, with some learners showing more variability than others.