Don't known if it's me,but seriously nothing is as stressful physically as being the first son in a poor family, when I said poor home am not talking about the extreme poor home that can't feed or resolve to street begging, if you can't eat what you feel like eating because of the amount such meal would cost but resolve to eat what would fill your stomach to save for tomorrow meal then you might be poor but there are levels to it.just like someone with a million in account might be said to be rich but in truth such person is poor because a little emergency might blow out the money in a seconds.
Now back to the discussion the worst being a first son is getting drain mentally with the thought of how to survive in Nigeria with your siblings on the other side.
You are consider to be a second parent in a poor home where you have to provide for the family with what ever you have if you are working,except you are the type that have a heart of stone who would say no,but it's being proven that 75% of all first son are quite, calm, introverted e.t.c
Even the cold one's are not left out because of feeling guilt and their conscience judging them later on in life.
Now imagine this scenario where the first son due to assisting their parents financial gets a job helping out in feeding expenses, then the junior one got admission into a university through the first son sponsor, finish schooling got a good job because he or she got a certificate but the first son is still doing meanie job, now what is the percentage that he would be compensated for helping out.
As a first son the strive to success and struggle to make it in live in order to help your junior ones and claim your place as the first son leave some emotional imbalance.am sure that most if not all first son in such home might at a time suffer depression.
Nice one