My mother left money to a man none of us know

Dear Delyara, My mother’s will leaves £20,000 to a man named Peter Wallace. None of us knows who he is. The solicitor says Mum added the gift five years ago while fully competent. There is an address. My sister immediately assumed an affair. My brother thinks Peter may have helped Mum secretly. I am simply confused. Mum was widowed for thirty years. She told us everything—or I thought she did. I searched the name online. There are too many. I drove past the address once and did not knock. An older man lives there. What do I say? Hello, my mother is dead and apparently you mattered £20,000 worth? Part of me feels betrayed by the secrecy. Another part is strangely glad she may have had a relationship or friendship that belonged only to herself, not to being our mother. Still, every time I think I knew her life, this stranger’s name appears like a locked drawer.