How do you change a toddler's diaper/nappy?

With an adult or teen sim click on the toddler, then click More Options, then click Toddler Care. Change Diaper should be on the right hand side of of the option wheel. It doesn't clean them though the way it did in Sims 3 (the only way to raise hygiene is to bathe the toddler) but if they use their diaper often enough it will get smelly and the sims around the toddler will get a negative moodlet.

Just testing.

"plopppo2;d-923408" wrote:
This could be the single-most aggressive question in Simming history.

I can't find anyway to change a toddler's diaper/nappy and am HIGHLY suspicious that it is impossible.

Toddlers are filling those thing up - because I can see them doing it when they like - but there is no option to change them.

It seems the only way to clean a toddler is to bathe them - is this right?

Click on toddler, choose More... and them Toddler Care...
Remember, changing their diapers won't raise their hygiene bar, so you'll have to bathe them.

Do babies need their diapers changed too?

@hunter_Iria yes, when they get stanky. When a baby is crying, you can click them to check what is wrong. When you select the interaction to check, pay attention to the thought bubble that comes up and it will indicate whether they need diaper change, food or attention.

Diaper change is pretty easy to determine though, as your sims will usually make reactions to the stink. lol

Do you use a changing table like in The Sims 2, or is it automated again?

@Hunter_iria no changing table, they just pick them up and there's a magical whirl and the baby has a new diaper (i really miss changing tables..*sigh*)
You click on the baby's crib and select to change the diaper from that menu. In TS4 all baby interactions/actions occur by clicking the baby/crib. Probably one of the most disappointing aspects of the game..but no sims game has handled babies all that well, I guess.

Thanks for the info, I really appreciate it!

I usually just give the toddler a bath; that way their hygiene stays good, too!

Use the toddler potty and start the training!