Ben picks up "Big Sister" Violet from school on Jan. 12. (©www.splashnews.com)
The tot, who made her debut in Los Angeles on Jan. 6, is their second, joining big sister Violet, 3, who proudly displayed her new status on the front of her T-shirt when Ben picked her up from school on Monday.
No word on their inspiration for the name Seraphina, which is based on the Biblical word seraphim, the highest rank of angels.
At least one baby name expert says we should expect to hear about the arrival of many more Seraphinas in the future.
"Ben and Jen really put Violet on the map," Pamela Redmond Satran explains to Us. "They transformed it from what people saw as a dowdy, old lady name to a really cute, modern choice."
What do you think of the name of the newest Affleck? Tell us in the comments section.
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