Gallery: Love across the pond: 10 American celebrities with British partners (BANG Showbiz)And as well as boasting Meryl Streep as her mother, Grace’s dad is artist Don Gummer, and she has siblings including actor brother Henry Wolfe and actress sisters Mamie Gummer and Louisa Jacobson. Meanwhile, Mark announced his engagement in June this year after it was first reported by outlets in May, when Grace was spotted wearing a diamond ring.