Solution
Reorder the paragraphs based on the ordinal number mentioned in each paragraph. Then, read the first letter of every sentence, which spells out “THIRD LETTER OF EACH CHILD.” Reading the third letter of each child’s name, in the new order, spells out “YOUR USER.” The answer is to submit your flavor’s username.
Please don’t share the solution in spec/dead chat, as several people there are trying to solve it on their own.