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AAP. 2015. Emotional development: 2 year olds. American Academy of Pediatrics. https://www.healthychildren.org/English/ages-stages/toddler/Pages/Emotional-Development-2-Year-Olds.aspx [Accessed August 2016]
CDC. 2016. Toddlers (2–3 years of age). U.S. Centers for Disease Control and Prevention. http://www.cdc.gov/ncbddd/childdevelopment/positiveparenting/toddlers2.html [Accessed August 2016]
Mayo Clinic. 2016. I’ve heard a lot about the terrible twos. Why are 2-year-olds so difficult? http://www.mayoclinic.org/healthy-lifestyle/infant-and-toddler-health/expert-answers/terrible-twos/faq-20058314 [Accessed August 2016]
Nemours Foundation. 2016. Your child’s development: 2 years (24 months). http://kidshealth.org/en/parents/development-24mos.html [Accessed August 2016]
Zero to Three. 2016. Toddlers and challenging behavior: Why they do it and how to respond. National Center for Infants, Toddlers, and Families. https://www.zerotothree.org/resources/326-toddlers-and-challenging-behavior-why-they-do-it-and-how-to-respond [Accessed August 2016]