。
She doesn't rest for even a moment.
Literal
She [topic-は] [a-little-while-ちょっとの間] [even-も] doesn't-rest.
ちょっとの間 ('a little while, a brief interval') is a productive frame — ちょっと ('a bit') + の (attributive) + 間 ('interval, span'). Combined with the emphatic も and a negative predicate, it creates the 'not even a brief X' scope — strengthening the negation by ruling out even the smallest case. Compare 一日も休まない ('doesn't rest for a single day') and 一秒も休まない ('doesn't rest for a second') — same emphatic-with-negative structure, different scales.