Lawyer to assist with pension claim

Hello parents, I'm seeking a recommendation for a lawyer well versed in handling pension claims / suits. My mother passed earlier in the year and was with her employer for over 20 years. She has a very large pension amount due to her estate that her employer has flatout refused to pay out. There's more details but I do not want to disclose in a public forum. Seeking a skilled lawyer to help fight for what's right here in my family's time of deep grief. 

Please send your referrals and recommendations! Located in Brentwood, and open to a lawyer/firm anywhere between Oakland and Brentwood. 

Thanks