What is the ruling on making up the four days that the questioner missed fasting in her childhood, given that she does not know whether this occurred before or after puberty, and does she have to feed a poor person for each day due to the delay in making them up?

The signs of puberty are: menstruation, emission of semen, growth of coarse hair around the private parts, and reaching the age of fifteen.

If you are unsure whether what you broke your fast for was before or after puberty, the original ruling is that there is no obligation for qada' (making up the fast) unless you are certain that you broke your fast after puberty.

The fundamental principle is the acquittal of one's responsibility. Therefore, you are not obliged to make up any fasts unless you are certain that you broke them. Nothing is required of you based on mere doubt.

If you are certain that you owe make-up days and you delayed making them up while knowing the impermissibility of the delay, then you must make them up along with a fidyah (expiation) of feeding a poor person for each day. However, if you were unaware of the impermissibility of the delay, then nothing is required of you.