My question involves landlord-tenant law in the State of: California

Today is Thanksgiving and my tenants have told me they are splitting up (husband, wife and 3 kids), and
will be moving out early from a 1-year lease to make living arrangements over 2 apartments.

The lease was supposed to expire in May 2014.

Here is what they want and here is my question:

• The husband has asked that I use the deposit to cover the proposed last month of the rent (December) so
that they can use current funds to get them both situated apart from each other. (There is no damage to the house
whatsoever (I inspected the place today) so I will not need to charge them anything).

• The Question... Is there any legal paperwork I should submit? A 30-day notice or anything? I'm ok with them leaving
early from the lease (I sympathize with their needs). They are already packing and may even be out earlier than Dec 31st.

Thanks in advance, as usual!