Thank you for your query.
As you are not able to trace the cat, I advise you to get your child vaccinated completely for rabies
with 5 doses on 0, 3, 7, and 14 days.
And at the same time you observe for any rash or fever, as there are chances of getting cat scratch disease
after the bite or scratch by a cat.
So consult your Pediatrician
Hope I have answered your query.