Early Childhood Education centres in Kenya face persistent staffing deficits that undermine their capacity for institutional growth, yet the specific pathways through which personnel management challenges constrain centre development remain poorly understood, particularly in devolved governance settings. This study examined how personnel management challenges experienced by ECE Teachers in Charge (TIC) relate to the growth of public ECE centres in Jomvu Sub-County, Mombasa County, Kenya. Grounded in Ecological Systems Theory and Resource Dependence Theory, the study employed a descriptive cross-sectional survey design using a convergent parallel mixed-methods approach. Census sampling included all 58 stakeholders: 11 Teachers in Charge, 44 class teachers, one Sub-County ECE Coordinator, and two County Directors. Data were collected through structured Likert-scale questionnaires and semi-structured interview guides. Instrument reliability coefficients ranged from a = .802 to a = .969, with a Content Validity Index of .89. The study achieved a 93.1% response rate (n = 54). Findings revealed severe personnel deficits, with a composite mean of 1.50 for TICs and no respondent confirming that teacher-to-child ratios meet recommended standards. Personnel management emerged as the strongest predictor of centre growth at both the TIC level (r = .787, p = .004) and the teacher level (r = .903, p < .001), with a dominant regression weight (Beta = 1.023, p < .001). Qualitative data traced this association through TICs' dual burden as classroom teachers and centre managers, unsustainable workloads, and the absence of teacher replacement after attrition. The study recommends that Mombasa County Government recruit additional ECE teachers on permanent terms and establish structured professional development for Teachers in Charge.