The most common and most likely answer to this crossword clue is the 10 letter word PAEDIATRIC
I've seen this crossword clue in The Daily Telegraph
P
A
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D
I
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More clues leading to the result PAEDIATRIC
Buddy explains!

The straight part
We know that "dealing with sick children" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dealing with sick children = paediatric.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.
What does PAEDIATRIC mean?
PAEDIATRIC adjective- Of or pertaining to pediatrics, the branch of medicine dealing with the care and treatment of children.