Try putting the toddler to sleep for a while half way through the day just to top up their energy needs. Once the toddler has gained some energy spend time skilling up, then bath, feed etc and put back to bed. it's really just about getting them into a routine lol a lot like real life I guess. Also toddlers can grab a serving from a plate of food left on a bench etc so have them feed themselves to save a bit of time.
You can feed toddlers harvestables, they don't fill them up much but give them a good moodlet and can stave of hunger for a little bit longer to help with more time for skilling. Toddlers can eat harvestables from their own inventory or the floor or your adult sim can give them harvestables from their own inventory.
You can also wake toddlers up in the middle of the night, have them go potty (once at L2), eat from food an adult prepared earlier and placed in fridge (drag plate of food from fridge to the toddlers feet and direct toddler to take a plate, then drag food back to fridge) and then put them back to bed, this way they won't need to eat etc when your adult sim wakes up so there will be more time for skilling.