The actress, who is now a mainstream film star, gave birth to Joseph Gunnar Lee in 2007 - and she admits she's still amazed that she was blessed as a mum.
The Cry Baby star tells BlogTalkRadio.com, "I wasn't planning on it. I had fantasies of having a child with my husband, who I'm celebrating 10 years with next month, but it was never a good time - I was always doing a movie or going on tour and singing and all the pressure of having a size-zero a** and all of that was there.
"I kept putting it off, and then, at 37, I went with my husband Jeff (Gruenewald) to host a Hard Rock Cafe event in Vegas and we gambled, won some money, drank some vodka, and we came back pregnant! Who gets knocked up at 37? That was amazing and it was completely unexpected."