If someone tries to dig up private dirt on you, tell them no thanks, that stuff is in the past. Some things should stay in the past. Not everyone needs to know everything about your life and your past.
To remember the reading きょ, we'll use "Little Kyoto." This will differentiate きょ from きょう, which is regular-sized Kyoto. Get it? You decide to bury all this private dirt from your past in Little Kyoto (きょ). That stuff is from when you were just a little 子 (こ) and you don't like to think about it.
Currently there are no similar looking kanji which exist in the WaniKani learning system