The most common and most likely answer to this crossword clue is the 9 letter word PLAYGROUP
I've seen this crossword clue in The Guardian
P
L
A
Y
G
R
O
U
P
Buddy explains!
The straight part
We know that "Toddlers kept engaged by this" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case toddlers kept engaged by this = playgroup.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 PLAYGROUP mean?
PLAYGROUP noun- A group of children who meet together for supervised play.
- A group of gamers who meet together, especially for role-playing games.