The most common and most likely answer to this crossword clue is the 5 plus 4 letter word NAPPY RASH
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More clues leading to the result NAPPY RASH
- Knock over empty potty; headstrong toddler may get it
- Sleepy? Fast becoming a fundamental pain for babies?
- Round rear of baby one’s gone in sharp pain, unfortunately?
- Sleep party ends with impetuous infant’s complaint
- A minor skin problem
- Baby’s complaint irks many perhaps but not me
- Spotted outbreak contracted from child’s waste container
- One of baby’s complaints – any perhaps treated out East?
- Edgy and unguarded, not having some sleep leads to irritation for babies
- Any sharp pain initially will upset and bother a child
Buddy explains!

The straight part
We know that "irritation for babies" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case irritation for babies = nappy rash.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.