Like @LiaRose1435, I like to micro manage all of my sims. So I have my toddlers on a schedule, but it also depends on how their parents are. So some of my toddlers have more free rein than others. Normally they are up no later than 8 am, eat breakfast, get bathed, go to the potty, then I let them play a bit.
After one of the parents will help with with a skill or two, they get read a book. Normally it's snack time, so they either get juice or cookies, and sometimes both. More playtime. The majority of my sims will start dinner around 5 - 6 pm, so that's when the toddler will eat as well. Play a bit more, story time, then in bed no later than 9 pm. And everything starts over the next day. :D