Finn Davey, who is 20 inches long, was born at 5:39PM on Thursday weighing six pounds and six ounces.
Finn Davey joins three older siblings -- five-year-old Liam Aaron, who was born in March 2007, four-year-old Stella Doreen, who was born in June 2008, and 10-month-old Hattie Margaret, who was born in October 2011. McDermott also has a 13-year-old son named Jack from a previous marriage.
Liam was born a week before the first-season premiere of Spelling and McDermott's Tori & Dean: Inn Love Oxygen reality series, and Spelling coincidentally gave birth to Stella a week before the third-season debut of Tori & Dean: Home Sweet Hollywood.
Tori & Dean: Home Sweet Hollywood viewers got their first peak at Hattie during the show's sixth-season premiere, which aired in November 2011 and included a special live peek into the family's home.
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