Tori Spelling and Dean McDermott welcome son Finn into their ‘kooky’ world, promise ‘wild ride’

And baby makes six for the Tori Spelling-Dean McDermott clan! A photo of Finn Davey McDermott's itty bitty hand wrapped around his mother's finger announced the arrival of the reality TV couple's fourth child together. "We are so excited to announce the birth of the newest member of the McDermott family," the surely exhausted new mom posted on ToriSpelling.com Thursday night.

Early Friday, McDermott — who also has a child with his first wife — posted an open letter to his third son on his website, welcoming Finn into "this crazy, whacky, amazing world full of joy, good times, bad times, love, loss, friends and foes — and that's just your brothers and sisters!" The 45-year-old promised the baby that his siblings will always be "full of love, laughter and energy. Quite frankly they're absolutely bonkers, too, but you're going to love them. Mom and Dad are a bit kooky, too — that's just how we roll. Not to worry though, we'll grow on you after a while. So strap on your Onesie, because it's going to be a wild ride."

It really has been a wild ride for Spelling, 39, and McDermott, who were both married to other people when they fell in love while shooting a Lifetime movie in 2005. (If you think this sounds a lot like LeAnn Rimes and Eddie Cibrian's story, you're right.) Just under a year later, their respective divorces were finalized and they got hitched. Their children were born fast and furiously: Liam in 2007, Stella in 2008, and Hattie in 2011.

In fact, Spelling — who has been hosting the TLC series "Craft Wars" — announced her most recent pregnancy in March 2012 — just five months after giving birth to Hattie. "I was shocked, obviously," she told People in April. "It was the second biggest shock of my life. The first was when they said Hattie was a girl when she was born, because we thought she was going to be a boy. And the second was that I was pregnant after my newborn had just turned one month old."

Always a little guilty of oversharing, the "Beverly Hills, 90120" star then detailed how she and McDermott chose to ignore her doctor's advice not to have sex until at least six weeks after her Caesarean section."You're going to have to talk to Dean about this because when we got out of the hospital, I was like, 'Specifically, the doctor said to wait six weeks.' And he was like, 'They tell everyone that. We didn't wait that long with Stella. Or Liam.'" She joked that she gave in because, "I didn't want him to think that the sex was going downhill."

OK then — moving on from TMI land … Spelling's pregnancy with Finn turned out to be her best one yet. "No morning sickness and I have energy — total opposite than the other three," she told People, though she definitely did seem ready to pop as she neared the end of her third trimester. In fact, for a recent trip to the supermarket, an exhausted-looking Spelling had to use a motorized scooter to get her shopping done.

A wild ride indeed. Well, congrats to the happy family!

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