Final answer:
The likely diagnosis is Acute Stress Reaction.
Step-by-step explanation:
The likely diagnosis for the 32-year-old patient with memory loss, insomnia, poor appetite, and difficulty performing daily routines is Acute Stress Reaction.
Based on the information provided, the patient's symptoms are consistent with acute stress reaction, which is a temporary condition that occurs in response to a traumatic event. Witnessing her child's fatal injury in a motor vehicle accident could have caused severe psychological distress and triggered these symptoms.
It is important for the patient to receive appropriate support and treatment to address her acute stress reaction. This may include therapy, counseling, and possible medication under the guidance of a mental health professional.