Babies (6 mos. and younger) – It is best not to make them wait very long. It is better to go to them when they are clearly
crying to let you know they need something (food, changing, or just comforting). When you answer their cries – not whimpers in the monitor – but actual cries, you teach them the world is an OK place and that they can trust you.
Young kids (18 months to three-years-old) – You can teach them about waiting every time you insist they do what you want them to do while they are loudly saying “no.” When you do this you are doing two things:
Letting them tell you they have their own ideas and are starting to think for themselves.
Making them wait until a better time to get what they want.