Get your taxes done using TurboTax

Sorry no.  Online browser version is only good for 1 return per account.   You would need to setup new accounts for each one.  You can use the same email for 5 accounts.  Each return will cost unless some can use the Free Edition.   Oh and you might need to use a higher version for someone to enter things like investments and self employment.  Only the Desktop installed program can do unlimited returns and efile 5.