She said: "She should keep breeding! She makes pretty babies."
However, Jennifer - who already has daughters, Violet, five, and two-year-old Seraphina, with Ben - recently revealed three children is enough and would like another girl.
The 39-year-old beauty - who grew up as one of three girls - said: "Three girls is a great way to grow up. I'm one of three girls and my little sister is awesome.
"It would be so weird to have a boy but it would be cool and different."
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Jennifer also revealed how her daughters aren't concerned about the gender of the baby but do want some input into the name.
She said: "They don't really care about the gender as long as we name it what they want it to be named. They like Ralphie, Frankie, Minnie Mouse, Daisy Duck or Rosemarie.
"Daisy Duck Affleck, I can see us going that way."