Evolutionary Parenting: Beyond the Sleep Training Narrative feat. Tracy Cassels | #43

Update: 2025-11-19

Description

Why does our society place more value on controlled baby sleep than on maternal support, proper feeding, or comfort?

Tracy Cassels began her influential work while pursuing her PhD in developmental psychology, coinciding with her pregnancy. She observed a profound contradiction between the widespread advice advocating for infant sleep training—even when pushed by some academics—and the robust findings found in developmental literature and her own research. This mismatch, which she initially felt was a foreign concept given her own background, became the critical momentum to start sharing her perspective publicly. This led to the launch of her extensive website, Evolutionary Parenting, roughly 15 years ago. This platform developed into an invaluable resource, providing detailed and thoroughly referenced information on nearly every topic related to infant brain development for parents. Tracy often interacts with families, some of whom bring along skeptical relatives or partners, seeking clarification on the evidence surrounding sleep practices. She approaches the topic by presenting an honest assessment of what the research confirms and what remains unknown, helping listeners discern the subtleties often missing from conventional advice. She argues that the findings against certain practices, such as sleep training, form an "incredibly strong circumstantial case" rather than a clear-cut legal link. Furthermore, Tracy contends that many sleep problems are misinterpreted as behavioral failures when they are actually symptoms of underlying issues like allergies, sleep apnea, or hormonal imbalances. Her most recent paper with Levita DeSousa advocates for researchers to adopt a much broader perspective, moving away from seeking a "one size fits all solution" and instead considering the full family dynamic, cultural influences, and health context when studying infant sleep.

Key Takeaways

● Sleep problems are often symptoms of underlying physical or psychological issues, not always primary behavioral faults of the baby or parent.

● The research focusing specifically on mothers and babies, particularly concerning clinical interventions and emotional connection, is significantly lacking.

● An overemphasis on controlled sleep in modern society leads parents to prioritize it over other critical nurturing components like love, comfort, and proper feeding.

● Some research proposes methods to help mothers suppress the natural anxiety they feel when hearing their distressed baby cry, counteracting an essential evolutionary response.

● Infant sleep should be viewed as a family dynamic influenced by culture, general family preferences, health issues, and the need for connection.

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Resources

● Tracy's Instagram: @tracycasselsphd https://www.instagram.com/tracycasselsphd

● Books by Tracy Cassels:

○ Finding Daycare: Navigating the Murky World of Child Care in Today's Society

○ https://www.amazon.com/Finding-Daycare-Navigating-Todays-Society-ebook/dp/B07PGDR6TC

● Evolutionary Parenting's website: https://evolutionaryparenting.com/ (Note: Some parts are currently missing due to a crash, but it will be restored soon).

Guest Bio: Tracy Cassels holds a PhD in developmental psychology and is the founder of Evolutionary Parenting. She co-authored a paper with Levita DeSousa, an attachment theory specialist at Monash University in Australia, focusing on how sleep training ignores the larger family dynamic. She is also a contributor to an upcoming academic book on sleep, edited by Jenny (who Greer has also written with), which includes chapters from Darshan Arves and LaVita DeSousa.