Aging issues

Sorry for the complicated post - but it's complicated. 

I had a Sims 4 toddler. Her skills were maxed out, and I was REALLY sick of her being a toddler. So I went to check on when her birthday was. Three days. It seemed maybe a little early in the year from what I remembered, but whatever - I was getting rid of her toddlerhood, so yay!  Three days rolls around and I throw her a party and do the blowing out the candles thing - except at first there's no option to age her. I repair the game and try again. I think it's fixed - the screen comes up asking me to choose a new aspiration for her. Except it won't let me. I click and it does a odd movement, like the aspiration icon is going to go up to the blank  aspiration spot, but then it doesn't. So I try several times and give up.

I go to check the calendar to try to figure out what is going on, and she's got no birthday scheduled at all. EVER. Ugh, but I'm flexible. I age her up using the CAS cheat. It accepts the new aspirations and I thought everything was hunky dory. Except it wasn't. 

I went to look at the calendar again, and her birthday is back on there in the place I remembered it being initially. Ok. Easy fix - I'll just age her back in the CAS cheat, store all her childhood belongings, and wait. Nope. I aged her backwards and she ended up with none of the skills she'd acquired. Which is probably my bad for not expecting and I could have lived with. But then it auto-aged her up again within a minute or so of gameplay, even though we were nowhere near when her birthday was supposed to be. 

Now I'm just confused. And nobody else seems to be having this issue. Unless they are?