Younger Sibling can Increase Your Blood Pressure

We are all aware of sibling rivalry; a study now indicates that a younger sibling can cause an increase in blood pressure in the older child. This study was published in the journal, Economics and Human Biology. The study, conducted in nearly 200 families from the Amazonian villages of Bolivia, found that a younger brother can increase blood pressure by 3 to 5.9 per cent while with a younger sister, the blood pressure increases by 3.8 per cent.What could be the possible reason for this increase in blood pressure?  According to the authors, the arrival of a new child is stressful for the older child.  The older child not only has to compete for attention from parents, he/she may also have to share the responsibility of taking care of the younger child.  
The rise in blood pressure may also depend upon the number of younger brothers, with a directly proportional relationship. 
The significance of this rise in blood pressure has yet to be determined with further studies.  Moreover, this effect on blood pressure seems to gradually fade away as a person grows older.  Thus, it may not have any long-term consequences on the person.  However, it does call for extra parental attention towards the older child on the arrival of the younger one. 
Reference: 
1. http://www.dailymail.co.uk/sciencetech/article-2232712/
Children-suffer-significantly-higher-blood-pressure-younger-brother-sister.html 

2. http://www.medicaldaily.com/articles/
13128/20121114/having-younger-brother-sister-risk-heart-disease.htm 

3. http://timesofindia.indiatimes.com/life-style/health-fitness/
health/Younger-siblings-send-your-BP-soaring/articleshow/17228258.cms