American Academy of Pediatrics

“Discipline As your baby becomes more mobile and inquisitive, she’ll naturally become more assertive, as well. This is wonderful for her self-esteem and should be encouraged as much as possible. When she wants to do something that’s dangerous or disrupts the rest of the family, however, you’ll need to take charge. For the first six months or so, the best way to deal with such conflicts is to distract her with an alternative toy or activity Standard discipline won’t work until her memory span increases around the end of her seventh month. Only then can you use a variety of techniques to discourage undesired behavior. When you finally begin to discipline your child, it should never be harsh. Remember that discipline means to teach or instruct, not necessarily to punish. Often the most successful approach is simply to reward desired behavior and withhold rewards when she does not behave as desired. For example, if she cries for no apparent reason, make sure there’s nothing wrong physically; then when she stops, reward her with extra attention, kind words, and hugs. If she starts up again, wait a little longer before turning your attention to her, and use a firm tone of voice as you talk to her. This time, don’t reward her with extra attention or hugs. The main goal of discipline is to teach limits to the child, so try to help her understand exactly what she’s doing wrong when she breaks a rule. If you notice her doing something that’s not allowed, such as pulling your hair, let her know that it’s wrong by calmly saying “no,” stopping her, and redirecting her attention to an acceptable activity. If your child is touching or trying to put something in her mouth that she shouldn’t, gently pull her hand away as you tell her this particular object is off-limits. But since you do want to encourage her to touch other things, avoid saying “Don’t touch.” More pointed phrases, such as “Don’t eat the flowers” or “No eating leaves” will convey the message without confusing her. Because it’s still relatively easy to modify her behavior at this age, this is a good time to establish your authority and a sense of consistency Be careful not to overreact, however. She’s still not old enough to misbehave intentionally and won’t understand if you punish her or raise your voice. She may be confused and even become startled when told that she shouldn’t be doing or touching something. Instead, remain calm, firm, consistent, and loving in your approach. If she learns now that you have the final word, it may make life much more comfortable for both of you later on, when she naturally becomes more headstrong.”
― American Academy of Pediatrics, Your Baby's First Year

“De Schipper, E. J., J. M. Riksen-Walraven, S. A. E. Geurts. 2006. Effects of child-caregiver ratio on the interactions between caregivers and children in child-care centers: An experimental study. Child Devel 77:861-74.”
― American Academy of Pediatrics, Caring for Our Children: National Health and Safety Performance Standards