Geary, who gave birth to Thicke's daughter earlier this year and is expecting another child with the pop star, posted a photo on Instagram that showed apocalyptic billowing smoke in their neighborhood.
"Our house is somewhere in there. I’m so sad but so thankful that we all made it out safe. Praying for everyone in Malibu, our home is up in flames ."
Geary, 23, included a broken heart emoji in the post.
She also wrote on Twitter that "My house & all of my belongings burnt down."
Thicke, 41 posted an Instagram photo of Julian, the son he had with ex-wife Paula Patton, crouching on Malibu beach.
The singer captioned it, "Contemplating next move...."
As Radar readers know, the lovebirds announced in August that they are expecting a second child together.
It was fast as Geary had just given birth to their daughter Mia Love in February.
As Radar readers know, Thicke and Patton struck a deal over son Julian after a bitter custody battle. They divorced in 2015.
The "Blurred Lines" singer started dating much younger Geary after he split from Patton.
Thicke has suffered a lot of tragedy as his father, Growing Pains star Alan Thicke, died suddenly of a heart attack at age 69 nearly two years ago while playing hockey in Los Angeles with another son, Carter.
Now Thicke and his baby mama have lost their home.
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