TikTok therapist sparks conversation on 'eldest daughter syndrome'

"Eldest daughter syndrome," a term describing common traits among oldest female siblings, has gained attention after a therapist's viral TikTok video highlighted eight key signs.

Licensed marriage and family therapist Kati Morton shared insights on the phenomenon during a recent appearance on NBC's TODAY show. While not an official mental health diagnosis, Morton defined it as "the unique pressures and responsibilities placed onto the oldest daughter in the family."

The eight signs Morton identified include:

1. Intense feelings of responsibility

2. Overachieving and driven personality

3. Excessive worry and anxiety

4. People-pleasing behaviors

5. Difficulty setting boundaries

6. Resentment toward siblings and family

7. Struggles with guilt

8. Challenges in adult relationships

Morton's TikTok video on the topic has garnered over 6 million views, resonating with many eldest daughters who recognize these traits in themselves.

Sara Stanizai, another licensed marriage and family therapist, runs a support group for eldest daughters. She notes that these women often act as "bonus parents" and bear the brunt of family pressures.

"Hearing each other's stories and also being heard ... what that's really telling you is you're not abnormal," Stanizai told TODAY in a virtual interview.

Morton explained the video's popularity, saying, "It spoke to people about a specific issue that they couldn't put their finger on."

When asked about research on birth order effects, Morton acknowledged, "In psychology, the tricky thing is there's not always a number you can put to something and have quantitative metrics," she said. "It really is dependent on the person and the family dynamics and how involved the parents were."