HESI developmental milestones study guide 2023

birth weight doubles by - 6 months birth weight triples by - 12 months birth length increased by 50% at - 12 months posterior fontanel closes by - 8 weeks social smile occurs at - 2 months head turns to locate sounds at - 3 months moro reflex disappears around - 4 months steady head control is achieved at - 4 months head turns to locate sounds at - 3 months rolls from abdomen to back and back to abdomen at - 5 to 6 months plays peek-a-boo after - 6 months transfers objects from hand to hand at - 7 months develops stranger anxiety at - 7 to 9 months sits unsupported at - 8 months crawls at - 10 months fine princer grasp appears at - 10 to 12 months waves bye-bye at - 10 months walks with assistance at - 10 to 12 months says a few words in addition to "mama" or "dada" at - 12 months birth weight quadruples by - 30 months