Children will not remember you for the material things you provided
but for the feeling that you cherished them.
Richard L. Evans

Allow them to be sad or mad

Children need to know that it's okay to be unhappy sometimes — it's simply part of life. And if we try to squelch any unhappiness, we may be sending the message that it's wrong to feel sad. We need to let them experience their feelings, including sadness.

You can encourage your child to label her feelings and express them verbally. Even if your toddler isn't talking yet, you can show her pictures of faces and ask her which one is feeling the same way she is. Young children will pick up very quickly on "affect" words such as "happy" or "angry." When they can put words to their emotions, they gain a whole new capacity to recognize and regulate their feelings. Don't try to solve her problems for her. Instead, just listen and help her talk through her feelings.

...you shouldn't overreact to your child's negative feelings. "It's normal for kids to become oversensitive or clingy or nervous at times because of something in their environment, but it's not an unhappiness."

Nguồn: How to raise a happy child (age 2 to 4.)