The more difficult one is probably “come here” vs “be quiet”. Unless there’s some way to tell the length of the last knock those two sound the same, and they’re both plausible responses to a “meet me” knock. “My room” and “tomorrow” have a similar issue, again being “we can meet, but you come to me” and “I don’t want to meet” responses distinguished only by the length of the final knock
But to be fair they’re 11/9 year old kids, hell yeah for making a secret pseudo-Morse-code
The more difficult one is probably “come here” vs “be quiet”. Unless there’s some way to tell the length of the last knock those two sound the same, and they’re both plausible responses to a “meet me” knock. “My room” and “tomorrow” have a similar issue, again being “we can meet, but you come to me” and “I don’t want to meet” responses distinguished only by the length of the final knock
But to be fair they’re 11/9 year old kids, hell yeah for making a secret pseudo-Morse-code