Sure, people can sue for anything. This is a sue happy country full of ambulance chasers.
But the rules are the rules. That is SOP for any company with contests or promotions, that employees and their family are excluded.
To win a lottery prize, you must follow all the rules of the game that determines a winner. But there are many more rules than stated on the website or playslip. The official rules. You may not see them, but they are always in effect. From the CA Lottery official rules:
“Disqualified Persons” means persons/Players prohibited by statute, regulation,
or contract with the Lottery from purchasing a Lottery Ticket and/or winning a
Lottery Prize or participating in a Promotion and/or receiving a Promotional
Award and includes:(1) persons under the age of 18 years; (2) members of the
Commission; (3) any officer or employee of the Lottery or the Commission; (4)
any officer or employee of the California State Controller’s Office who is
designated in writing by the Controller as possibly having access to confidential
Lottery information, programs, or systems; (5) any Contractor or subcontractor
prohibited by the terms of a contract with the Lottery from playing Lottery games;
and (6) any spouse, child, brother, sister, or parent who resides in the same
household as any person described in numbers (2), (3), (4) or (5) herein.
Further, prize Claims resulting from winning California Lottery Tickets purchased
by Disqualified Persons are invalid, regardless of the identity of the Claimant.
You don't have to sign to acknowledge them, but they are always in effect. Just like other rules or laws, you don't have to sign that you accept a speed limit, but if you break it, you will be charged. If you win and try to claim your prize, they have to validate the ticket and also verify if ALL the rules were followed and the ticket was legally obtained. Payment is not an entitlement.
So if you want to play the lottery and your parent works for the lottery or one of its partners, you are SOL pal.