A spokesperson confirmed that the baby's name is Bear Winslet, who was born at an NHS Hospital in Sussex Dec 7, reports aceshowbiz.com.
Kate is also a mother to 13-year-old daughter Mia from her marriage with film producer Jim Threapleton and a 10-year-old Joe with director Sam Mendes. Bear is her first child with husband Ned Rocknroll, whom she got married to last December. The couple announced the pregnancy in June.
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