First, I get that you note “Child” 1 thru 7 to indicate offspring. Really, they’re adults though and I start my framing as such.
Adults are responsible for their decisions. Working gig jobs instead of a more traditional job, ethical issues, accepting jobs they aren’t suitable for or which have low/no compensation are all factors adults would have to consider.
The only person who seems to be obviously struggling despite decent planning and actioning (based on minimal descriptions provided) is child 1. Even that logic is tenuous depending on how long they’ve been attempting and failing in one industry while another is potentially a better fit for them that for some reason, ego or other, that they won’t consider. The rest are employed, with situation and compensation consciously accepted by each.
And I would also consider a human relationship element. If I have strong reason to believe giving all to one person would turn the other six against them in the form of lawsuits or violence, I might consider skipping inheritance altogether and give it to some charity. I suppose the amount of money and reason it can’t be split into multiple portions would also play a part in that decision.
Second from final thought, I do have a lot of siblings. Not quite seven but close. If our parents were to say, “hey, we only have enough money to give one person a meaningful inheritance, what should we do?”, I am confident nearly all of us would ask that they give it to the youngest who is still working through college and drowning in student debt. The rest of us have made our decisions on education and careers pursued, jobs accepted, lifestyle balanced with ability to support it. Not the spirit of your rigid scenario, but just pointing out another way of approaching the issue that was bricked out in the setup.
And final thought. Toss the rigid scenario aside and jobs/salary are not how I would hope to decide to divide assets among inheritors. I hope I have relationships with all my future offspring that go beyond simple sum of dollars.