Julia Haart breastfed her brother.
The 'My Unorthodox Life' star - who has Batsheva, 30, Shlomo, 27, Miriam, 23, and Aron, 15, with first husband Yosef Hendler - admitted it was a "mindf***" when her mother asked her to nurse her younger sibling Shlomo, now 29, when he was born a few months after her oldest daughter.
Julia, 52, told Amanda Hirsch on the 'Not Skinny but Not Fat' podcast: “You wanna hear a real mindf***?” I nursed my brother.
“My mother’s like ‘Oh, you’re already nursing your daughter, take this one too’ — and so I ended up nursing my brother and my daughter. Now that’s a mindf***.”
Until 2013, the fashion designer was a member of the Haredi community, a branch of Orthodox Judaism which opposes modern values and practices.
Julia explained that in "her world" wet nurses - women hired to breastfeed another woman's child, a practice which largely died out in the 20th century - still existed but she was a "time traveller" and people would need to be in a different period to "understand the world [she] used to live in".
The former Elite Model Management CEO admitted she had spent her "entire life" questioning her beliefs, albeit "silently", but the "beginning and end" of her decision to walk away from the faith was when Miriam came out as bisexual.
She said: “No one could convince me that she was somehow flawed.
"When she started questioning [the beliefs] that’s when I realised it’s not [only] me, it’s the system.”
Julia's marriage to "sad man" Yosef had been arranged for her, and though she hadn't wanted to be with him, she joked her "lovely" former spouse turned out to be much better than her second husband, Silvio Scaglia, who she filed for divorce from last December after two years of marriage.
She quipped: “The guy I was forced to marry is a much nicer one person than man I chose. Go figure that one out.”