Tia Mowry: Sister Tamera's baby is due any day now!

Set to welcome a baby boy any day now with husband Adam Housley, Tamera Mowry has the best labor and delivery coach around: Her twin sister and fellow mom, Tia Mowry!

Anxiously awaiting the arrival of her nephew, Tia Mowry, 33, told Us Weekly at the Oct. 18 launch of Tori Spelling's new Little Maven collection that her sister's due date is imminent. "I will be in the room with her coaching her," Tia -- who appeared alongside her twin on the '90s sitcom Sister, Sister and now costars on STYLE's Tia & Tamera -- said.

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Attempting a natural birth, Tamera will try to deliver without drugs -- something her sister, who had a C-section when delivering son Cree in 2011, isn't optimistic she'll be able to do.

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"She is my sister and we can't take pain. Pain and us, we just don't mix!" jokes the former Game actress, who married Cory Hardrict in 2008. "She is trying to be brave, which is good . . . but I don't think she is going to make it."

VIDEO: Tamera Mowry tells Us about plans for motherhood

As the extended Mowry family expands, STYLE network reality star Tia is having fun keeping up with her own 15-month-old. "He is saying more words than the average 15 month old," brags proud mom Tia. "He says 'night night,' 'bath time,' 'ball,' 'dog,' 'mama,' and 'dada.'"

And baby No. 2 may not be too far off, if Tia has her way. "It is a topic in our house every single day. I'm ready but my husband is on the fence -- and of course it takes two to tango!" she tells Us.

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