Knowledge on the transition to adulthood of undocumented immigrants arriving in childhood primarily derives from the experiences of minors arriving below the age of 13 years—or the 1.5 generation. The transition to adulthood of the 1.25 generation—those who immigrate between the ages of 13 and 17 years—has been largely missed. This article examines the salient challenges legal exclusion, or “illegality,” creates as the Mexican and Central American 1.25 generation launches into adulthood and the extent that “illegality” disrupts their envisioned futures. Drawing on interviews with 40 undocumented 1.25 generation young adults in Illinois, three distinct patterns were identified: (a) 1.25 generation participants who enrolled in U.S. K–12 schooling, (b) 1.25 generation men who never-enrolled in U.S. K–12 schooling, and (c) 1.25 generation women who never-enrolled. These patterns were shaped by the reasons for their migration, whether the migration process was gendered, and their expectations for adulthood. This article contributes to a more complete picture of the challenges childhood arrivals experience at a critical point of transition in the life course and the sources of variation. Moreover, attention is brought to the timing of immigration—the life-stage when a minor immigrates—as a source of differentiation warranting further consideration.

关于童年时期无证移民到成年过渡的知识主要来自未满13岁（即1.5代）的未成年人的经验。在很大程度上，人们没有想到1.25代（移民年龄在13到17岁之间）到成年的过渡。本文探讨了墨西哥和中美洲1.25代人成年后法律排斥或“非法行为”带来的严峻挑战，以及“非法行为”破坏了他们预期的未来的程度。根据对伊利诺伊州40名无证的1.25代年轻人的采访，确定了三种不同的模式：（a）1.25代参与者参加了美国K-12教育，（b）1.25代从未参加过美国K-12教育的男人和（c）1。从未入学的25代女性。这些模式是由其迁移的原因，迁移过程是否按性别划分以及对成年期的期望所决定的。本文有助于更全面地了解儿童期到达者在人生过程过渡的关键点所经历的挑战以及变化的根源。此外，人们关注移民的时机（未成年人移民的生命阶段），作为有区别的来源，值得进一步考虑。本文有助于更全面地了解儿童期到达者在人生过程过渡的关键点所经历的挑战以及变化的根源。此外，人们关注移民的时机（未成年人移民的生命阶段），作为有区别的来源，值得进一步考虑。本文有助于更全面地了解儿童期到达者在人生过程过渡的关键点所经历的挑战以及变化的根源。此外，人们关注移民的时机（未成年人移民的生命阶段），作为有区别的来源，值得进一步考虑。