The present article can serve as a model to help clinicians better understand and recognize markers of cognitive and social-emotional development in young children. The anticipatory guidance in this document is based on the typical development at each chronological age. Corresponding milestones in the domains of cognitive and social-emotional development are outlined in Tables 1 and 2. The separation of cognitive and social-emotional milestones into discrete categories is sometimes artificial because the two domains are inextricably linked. The milestones tables generally use the upper limits of the normal range to place each attainment, with the age range of attainment in brackets.  Corresponding milestones in the domains of cognitive and social-emotional development are outlined in Tables 2.  

While many people are quite aware of the chronological sequences for gross motor, fine motor and speech-language skills, knowledge about the less visible domains of cognitive and social-emotional development is often limited, for both physicians and parents , and has been missing or inadequate in the charts and references used by physicians for training and clinical work. There is a great need for physicians to be familiar with the early signs of social and/or cognitive impairment that might be the first indicators of conditions such as autism or intellectual disability, so that they can refer such children for further assessment and intervention. The present document should not be used as a developmental screening tool. Clinicians should use more specific and validated instruments for this purpose, such as the “Parents’ Evaluation of Developmental Status” (PEDS) or the “Ages and Stages Questionnaire” (ASQ), which have moderate to high levels of sensitivity and specificity. You have a great opportunity to find cephalexin antibiotic to feel one lucky customer.  


Cognitive and social-emotional milestones, 18 months to five years of age

Age Cognitive milestones Social-emotional milestones
18 months Explores from ‘secure base’ of caregiver (7-24 months) Imitates real-life activities using realistic props (15-18 months) Simple pretend play mostly self-related (13-24 months) Determined to do things independently (12-24 months) ‘Clings’ to parent (16-19 months), uses transitional object (12-24 months)  Frequent temper tantrums (18 months) 
2 years Begins to problem-solve without physical rehearsal (12-24 months) Searches for hidden object after multiple displacements (21-22 months) (12) Symbolic representation (12-24 months) Pretend play begins to be directed to others (13-24 months) Noncompliance (12-24 months), temper tantrums, and aggression peak (30 months) Negativism ‘no’, possessiveness ‘mine’ (19-24 months) Social referencing, empathy: Tries to comfort other who is upset (12-24 months) Enjoys parallel play around other children, may offer toy or smile (13-24 months)
3 years Object constancy, separates easily (2-3 years) Symbolic pretend play: Substitutes objects for other things (25-30 months) Bedtime fears and nightmares (24-36 months)

Names 1 colour, counts 2 objects, sorts shapes, compares 2 items (30-36 months)

Social role play, doll as playmate (31-36 months), imaginary friend (3-7 years) ( Initiates interactions with peers, cooperative play, shares toys (2-3 years) Understands rules (tells dolls, friends) (24-36 months) Able to talk about emotions and situations that elicit them (24-36 months) Feels guilt for hurting other child and may try to make things better (24-36 months)
4    years5    years Theory of mind established (3-4 years) Simple time concepts, plans ahead (3-4 years)

Identifies rules for problem-solving, tries solutions before frustration (3-4 years) Generalizes rules from one situation to another (3-4 years)

Verbal self-talk changes to internal dialogue to solve problems (3-4 years)

Counts 4 objects, categorizes objects, understands opposites (3-4 years)

Takes turns in conversation, listens to other’s point of view, responds appropriately (4-6 years) Pre-literacy skills: Knows alphabet song, recognizes and produces rhymes (2-5 years), learns letter sounds and names (5-7 years) Pre-numeracy skills: Counts 10 or more objects

Elaborate fantasy play (eg, superheroes) (3-4 years) Shows increasing emotional regulation over anger, aggression (4-6 years) Can resolve conflicts with discussion and negotiation (4-6 years) Empathy: Might often offer comfort and sympathy to peers, listen to others (3-4 years)

Understands moral themes (right and wrong) in stories (3-4 years)

Usually compliant, shame and guilt if misbehaves (3-4 years)

Initiates separations from parents, plays away for several hours (4-5 years)Noncompliance rare, follows group rules, understands games with rules (4-6 years) Develops sense of conscience, strict about rules, insists on them with peers (4-6 years) Understanding another’s perspective brings aggression under control (3-6 years) Can display emotions other than the one felt underneath (3-6 years)