YOU SAID:
If the cap fits, let them wear it
INTO JAPANESE
キャップが収まる場合は、それらを着用させて
BACK INTO ENGLISH
If the cap fits, let them wear
INTO JAPANESE
キャップが収まる場合は、それらを着用させてください
BACK INTO ENGLISH
If the cap fits, let them wear
That didn't even make that much sense in English.