"As we thank the angel of a woman that carried our miracle baby boy for us, we pray for everyone who struggles to reach this joyous milestone. York Banks Asla, welcome to the world. (sic)"
The 42-year-old supermodel previously revealed she has had to endure "traumatic" rounds of fertility treatment in the past.
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She said: "When I turned 40, the one thing I was not happy about is that I did not have kids. I'm like, 'Damn, the clock is ticking!' When you're like, 'OK, I'm just going to do it,' then it's not so easy as you get older."
"I've had some not happy moments with [IVF], very traumatic moments. It's difficult as you get older. It's not something that can just happen."
- Bang! Showbiz