This study aims to: (1) describe children’s participation in activities fostering their development, (2) document parental concerns about their children’s development, and (3) explore the influences of family characteristics on children’s activity participation and parental concerns. We conducted a phone survey with parents of children aged 0-5 years (n = 895). Survey results are presented as weighted proportions for the parent’s age, sex, and area of residence. Statistical comparisons were made using chi-square with p < 0.05. Most children were exposed at least weekly to fine motor (85.1% ± 2.4%), physical (83.0% ± 2.5%), and reading (84.2% ± 2.4%) activities. However, only a small proportion were exposed to those activities daily (49.7% ± 3.3%, 35.4% ± 3.2%, and 32.4% ± 3.1% respectively). Many (46.8%) parents had concerns about their children’s development. The most frequent domains of concern were communication skills (22.8% ± 2.8%), affective and behaviour skills (22.1% ± 2.7%), and autonomy (19.6% ± 2.6%). The proportion of parents having concerns was higher among families with lower incomes. The small proportion of children exposed daily to activities fostering their development, and the high proportion of parents with concerns about their children’s development are alarming. The integration of health and education services and the use of best practices fostering children’s development at home, at school, and in daycare centres is needed.