It will all be explained 
although it’s no a spoiler it’s so that the mother can prover to her daughter/son is magical so that the MC has some proof that it’s not a prank if you get what I mean. So it’s more like
“I know this is a lot to take in and is hard to believe. So here is a puzzle which can only be solved with some who has magical abilities”
Does that make sense? Obviously against I’ve done some planning it will be explained better it’s just so the MC doesn’t seem so gullible.