One didn't live long if one was weak.
That is what they were taught from the start of their young age.
Weakness was exploited and only the strong would survive. Weakness got you hurt, it got you in trouble, and there was no place for it.
Akeelah knew how to continue living on, she knew how to be strong, she knew how to survive. It was something someone her age had to learn quickly living through the experiences she had lived through. Away had gone the innocence and the childlike traits, and in their place was something that was far older then it should have been, fearlessness and the notion that one must get the other before they got them instead.
There was nasty habits that had to be made in order to survive; learning to fight before learning to fly, knowing where to hit to cause the most damage, and never ever allowing anyone to see you showing any weakness.
After the war was ended, and the four Princes reunited, the Morningstar reinstated to his position among the Host, and Father returning with Aunt at His side there was not a day during those months that followed that reminders of all of their mistakes didn't come to be in their line of sight.
Most were in the form of a little fledgling who had learned to survive on her own.
Michael saw the way she would survey her surroundings before allowing herself to be distracted, he saw the way that she always found a way to escape if the need arose to, and he saw the little muscles tense when someone she didn't know step close to her as though waiting for the other to attack first.
Lucifer saw the way she kept to herself, choosing to hum under her breath instead of for others to hear, how she made sure that no one underestimated her as she moved about fearlessly, how she always looked around her carefully as though waiting for the other foot to drop.
Gabriel saw it in her smile, it was always hiding something behind it, something with intent to never be caught unawares, he saw it in her interactions with others around her making sure she kept them at arm's length as best as she could to ensure they couldn't get in close enough for the possibility they may strike.
It was Raphael that saw things start to change, he had seen the way she shied away from comfort and made sure to be there when it was needed. He saw the way she would keep to herself and would find different things to draw her out again. He was the first one to help her after she saw someone from a hidden past, the first one to see her fearlessness crumble around her, to see the perceived weakness and encouraged her to let it out without hiding it again.
To show her that weakness was just as important to surviving as strength was.