A nurse is teaching parents of infants about the concept of object permanence in infants. Which statements should the nurse include in the teaching? (Select all that apply.)

A. Object permanence starts to develop around 4 to 7 months and is not fully developed by 6 months; this statement is inaccurate. B. Understanding object permanence is indeed a significant milestone in cognitive development, indicating that the infant can comprehend that objects continue to exist even when not seen. C. Playing peek-a-boo is an excellent way to reinforce the concept of object permanence, as it helps infants learn that people or objects can reappear after being hidden. D. Before developing object permanence, infants do think that objects cease to exist when out of sight, which demonstrates their cognitive limitations at that stage. E. Object permanence typically begins to develop around 4 to 7 months, not at 12 months, making this statement incorrect.