Quick sidebar, I don’t mean to drag this off-topic, but a question… How about a 4-year old? seriously.
My daughter is better with math at (almost) 4 than I was at 7+… addition and subtraction were dead simple… she learned multiplication by herself, and has it down pat, all the way up to 12x12 for all of them, anything 10X/100X as those are easy… pretty good with division, basic fractions, she understands square roots, and got the concept of primes instantly. She intuitively got left/right swaps when giving directions while facing someone… and, this one shook me a bit TBH, the other day she told me that because she had a first day of her life, she’ll also have a last day. This is NOT something we told her about…
So yeah… is anything safe for her to listen to? I want to give her every advantage I can.