The Garden State mom shares more about where things stand with her daughters' half brother.

Create a free profile to get unlimited access to exclusive videos, sweepstakes, and more!

Danielle Staub's little girls, Christine and Jillian, have grown up right before our eyes, but, it turns out, there's another young person in The Real Housewives of New Jersey mom's life who also plays an important role. Recently, she shared that her two daughters have a half brother, Billy, via their dad and Danielle's ex-husband, Thomas Staub.

She shared the news on Instagram in a throwback photo of Billy with Christine, writing last month, "They are one year and 2 days apart and the memories of these 2 continue to grow. I am #blessed to have an amazing #son and 2 #daughters. Soon they will celebrate their birthdays. Please send them both #birthday #wishes. #birthday for my sweetness is 12/4 and for my Billy 12/6 so-much #love #friendship #family #blessed #fun #memories #bigbrother #bigsister #love #kindness."

Following that reveal, Danielle, who split from her ex in 2007 and is currently engaged to Marty, spoke to The Daily Dish recently a bit more about her relationship to him, which you can watch in the video above.

More on Danielle's daughters, below.