If you have siblings, you may well reflect on your own childhood and recall instances where you felt great injustice; perhaps about having to always do 'baby things' because of your younger sibling(s), or living in constant fear of missing out. Maybe even now as an adult you still notice that subtle rise of competitiveness between you?!.
Competitiveness between siblings is not uncommon, however constant bickering, comparison and competition for your attention can be exhausting! Here is a great little article with 6 handy parenting tips, that may ease some of that tension.