A 2 year old or any child really should bathe daily to keep clean.
If the 2 year old child is still in diapers then you should always give them a bath every night because of the urine and poop that would get against their skin so it's best for hygiene reasons to bathe a 2 year old or any child daily at least once per day.
If you happen to forget to bathe your 2 year old child for one day it's not gonna harm them but make sure to always try and bathe the 2 year old at least once per day.
Also change their clothes everyday as well as they will get dirty and if someone sees the child dirty often and wearing the same clothes they can turn you into CPS and then your child could be taken away due to neglect.
I always bathed my children everyday when I had to bathe them and I make sure they take a bath everyday now themselves to keep clean even though they sometimes fight me or throw a fit when I tell them it's time to take a bath.
Taking a bath or shower is needed to stay clean especially if the child is still in diapers and peeing on themselves and pooping on themselves.
Being in diapers makes their groin area dirty even when you change their diaper often and wipe them.
Some urine can be leftover on their skin and it needs to be washed off in a bath.