Toddler frustration

I think that would work, if the toddler didn't keep mucking about. He (toddler) keeps trying to nap, eat play with toys then the parent keeps waving his hands in the air, but nothing is in the way
hmmm might have to adopt him out at this rate
i would bake a cake and age him up, but my sim is too tired to bake!

Oh wow... the number of times I have sat at my computer literally screaming profanities at my sims as they wander around doing dumb stuff instead of following the very clear instructions I gave them to care for their toddler.

One trick I have found that works sometimes is play as the toddler. Another is don't be afraid to jump between sims to complete an action. Click into the toddler and ask mommy for food, click in mommy and cancel anything else in her queue until all she has up is Feed The Kid, click into the kid to make sure they don't wander off. Teamwork!

autonomy off, debug/reset sim when they get stuck doing some nonsense thing instead of intended
works so far with no problems

I've never had toddlers be that hard to take care of. So it's possible you're experiencing a bug. Looks like there are a couple reports of bugged toddler interactions, you might check those out and see if they sound similar:

https://answers.ea.com/t5/Bug-Reports/NEEDS-SAVES-My-sims-won-t-take-care-of-their-toddler/td-p/9418528

https://answers.ea.com/t5/Bug-Reports/OPEN-Toddlers-can-t-be-put-to-bed-read-to-sleep/td-p/8142086

If it's not a bug, some other things to check:

Toddler traits matter a lot in how they behave. "Independent", and "wild" toddlers are the least cooperative, I've noticed in my games. It can be very hard to get them to do what you want them to do. Locking the door to the room helps keep them from queuing up some other activity elsewhere on the lot and makes them (and their parents) a little more manageable.

Dragging food directly in the toddler's inventory and then directing to them to eat it from there sometimes works better than putting it down somewhere and sending them to eat it.

Have you tried turning off autonomy completely for all sims in your household? If you try that and they still cancel your commands, there is probably either a routing issue or a bug.

If you are okay with cheats, you can use "testing cheats on" and then shift+click on each sim and choose "make happy" to restore their needs and give you a chance to figure out what's going wrong before someone dies or gets taken away.

Control the toddler as much as possible to keep them from starting something the parent won't be able to interrupt.

Some of us are having a bug where the parents keep having routing issues trying to take the child to bed. If you find you have that problem, the workaround is to make both the parent and child walk into the bedroom separately (using "go here") and then select the "read to sleep" or the other put to bed option.

High chairs are hard to use. I usually put plates of food out on the counter and direct the toddlers take a serving themselves. I haven't used a high chair in a while but I think I had learned that choosing "get food for" or similar wording on the high chair would result in the parent both putting food out and putting the toddler in the chair. Putting the child in the chair first and then trying to get food would usually result in the toddler asking to be taken out and the parent canceling the get food command to oblige.

I haven't had a problem with baths but my sims do have routing issues bathing dogs in small bathrooms, so maybe make sure there's enough space around the tub?

A couple more issues I've run into:

Sometimes if the toddler bed is pushed up against a wall, the parent will act like they can't get to the bed. It seems like they pre-choose a side, and then cancel if they can't reach the side they chose. It seems like which side they pick initially is random. But after that, they always pick that side. So once they decide they can't reach the bed (because the side they chose is against a wall), they always say they can't reach it, no matter how many times you try. Moving the bed away from the wall, or even pushing it up against the opposite wall, so that the previously blocked side is now accessible has fixed the problem in my game many times. It's really weird.

Bathrooms are sometimes the worst for routing issues. The sim washing the toddler need to kneel next to the faucet end of the tub, so make sure that's not blocked by a sink or toilet or something.

If there are two caregivers for the toddler (for example, two parents) sometimes they both try to do something with the toddler at the same time and the game cancels the action for one or both of them. Make sure one of the adults is busy doing something else before having the other take care of the toddler.


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Edit to add one more idea.

Is there a stereo on the lot? Sims (toddlers included I think) will wake up and get out of bed if the stereo is playing, even if it is in another room. So that's one more thing to check.

Thank you, everyone

I'll rearrange the furniture, and I did try turn autonomy off, which helped a bit. My broke sims bit the bullet and hired a useless nanny and had to fire her after she left the toddler stuck in the highchair :O and ignored the other one. The second nanny was amazing and cooked for the family! They had twins, so much for just two kids for their family lol as they already had one

I was tempted to run away and leave them to it and play another household until they got to child stage, but they only have one day to go, and I managed to get the parents to use their leave time and take shifts sleeping. Man what a mission!