TRAUMA

We have moments in our lives when we experience trauma. Some are major traumas, others minor.
Definition of a trauma according to clinical EFT using eftuniverse:
A trauma is a bad event, but what exactly is the dividing line between a bad experience and a traumatic experience?
In clinical EFT workshops (emotional freedom techniques), we use 4 criteria to describe a traumatic experience:
A perceived threat to a person's physical survival
The inability to process the event, resulting in a feeling of powerlessness
The feeling of isolation in a situation (the feeling of being completely alone)
the complete violation of expectations

It is clear that a car accident, rape, or physical attack does meet the criteria for a traumatic event. Although many experiences from your youth that you barely remember may also contribute to trauma.
There are many examples of this.
For example, a woman, 45 years old and a psychotherapist attending an EFT workshop.
She says that growing up, she really looked up to her brother. But he was quite harsh with her. He was 6 years older than her. One day, when she was 3 and he was 9, he wanted to have a wrestling match with her. He won and lay on top of her. She could no longer breathe and panicked. He just laughed seeing her panic. She almost fell unconscious when he finally rolled off her. She started crying uncontrollably. Her mother entered the room and she tried to explain what happened. He (her brother) told their mother that nothing special had happened and indicated that she was just a crybaby. Then the mother said to her; "Big girls don't cry."
This event meets all 4 criteria of a traumatic event, according to clinical EFT.
Most people have experienced similar events in their youth that meet these criteria. Some have many, others have only a few of these types of events.

During EFT we often work on healing the emotional impact of these events.
It can take a surprisingly "minor" negative experience to traumatize a child. In a series of studies called "the Still face" experiment by Harvard psychiatrist Edward Tronick, the effect of a child whose parents were emotionally withdrawn was examined (Tronick, Als, Adamson, Wise, & Brazelton, 1979;Tronick, 1989). He instructed the mother of the baby, about 6 months old, to keep her face impassive rather than interacting with her baby. When the mother kept her face motionless for a short period of time, instead of constant interaction of facial expressions (which we unconsciously use continuously for connection), the babies noticed immediately. When the babies did not receive facial communication from their mothers within 2 minutes, they became increasingly irritated. Then sad, and finally they began to move in uncontrolled despair. While the mother did nothing to hurt the baby. The mere withdrawal of connection was enough to produce extreme emotional distress.

Babies cannot regulate their own emotional state, let alone their heart rhythm, hormone levels and their nervous system activity that goes along with emotions (van der kolk, 2014, p.112). They depend on cues from adults around them to produce that regulation. Attachment produces a stable heart rhythm and low levels of stress hormones. An interruption of the connection with their caregivers produces spikes of stress hormones, as well as dysregulation of the nervous system and heart rhythm.
Tronick's work shows that it is not necessary to hit or abuse to influence a young child. The simple absence of emotional comforting cues from caregivers can be traumatic.
In other words, you may come from a very loving family or have a very happy childhood, but...
It can take a surprisingly small disconnect from mom or dad to upset a young child.