Well, first of all, hashcat does not support any kind of online password guessing. That means you will have to type any generated password by hand.
It is possible to generate word lists though by using the --stdout parameter and piping the generated data into a file. On the other hand you could use something like python for this purpose, if you are familiar with programming.
For your case, it you could use a mask attack like this: hashcat --stdout -a 3 asshole?d?d?d?d
Or use a specific rule file, that only appends valid date combinations.
I don't think that this will help you though, as I would expect Google to block you from guessing the password after too many failed attempts. Your best bet is probably to factor in the known DOBs you got available.
It is possible to generate word lists though by using the --stdout parameter and piping the generated data into a file. On the other hand you could use something like python for this purpose, if you are familiar with programming.
For your case, it you could use a mask attack like this: hashcat --stdout -a 3 asshole?d?d?d?d
Or use a specific rule file, that only appends valid date combinations.
I don't think that this will help you though, as I would expect Google to block you from guessing the password after too many failed attempts. Your best bet is probably to factor in the known DOBs you got available.