Rachel Fuda and John Fuda are expanding their family! 

The Real Housewives of New Jersey couple is expecting a new baby, an addition who will join their three other kids: daughters Gianella Jolie, 4, and Giuliana Rose, 2, as well as Jaiden — John’s 17-year-old son from a previous relationship whom Rachel adopted.

To help celebrate their baby-to-be, the Fuda family posed for a family photo shoot on the beach, pictures from which they’re sharing with PEOPLE first.

“We’re so excited,” Rachel, 33, says exclusively of her happy news, which she first shared with her RHONJ castmates on the season 14 “Off the Rails” special, which aired Sunday, Aug. 12. “We’re ready to be a party of six!”

“John and I always felt like our family wasn’t complete,” she continues. “We actually have a table in my kitchen and when we sit down for dinner, there’s one empty chair. And we always kind of looked at each other like, ‘Oh, it’d be nice to fill that seat.’ So we always had the room for one more in our home and in our hearts, and we’re both just so happy to be welcoming another baby into the family. It felt like it was time.”

RHONJ viewers know Rachel has made no secret of her desire to have another child.

In season 13, her first on the Bravo series, Rachel spoke to John about going again through the process of IVF, which she used to conceive Gianella and Giuliana. “The clock is ticking,” she said then, reminding him that they had five embryos still viable for transfer. “I just feel like, four kids, that’s a good number. The time is now. This is like, a year process. I want to do this and be done.”

Though John was reluctant at the time, Rachel tells PEOPLE they started the process again once cameras went down on season 14.

It wasn’t easy. To prepare for the transfer, Rachel first has to come off the arthritis medication she takes to treat the chronic illness, symptoms of which she first started experiencing as a kid. She then had to make sure her body would be able to accept the transfer, which proved challenging.

“There’s so many things that have to go right when you’re going through IVF, and this time around, there were a lot of roadblocks for us,” Rachel says, explaining that she struggled to get her cycle and lining “on point” at first. “It took a couple months of us working with my doctor to figure out when this could actually happen for us. And it was really frustrating because it just kept getting delayed.”

Just when Rachel had given up hope, she got the go-ahead. “I thought, ‘This is my last shot. If this doesn’t work, we’re done,’ ” she recalls. “Because first of all, it costs a lot of money. But second of all, you’re on all these medications that just throw your body off. I was hormonal, breaking out so bad, tired and on edge; my mood was going up, down, up, down. I just felt like, ‘I can’t do this anymore.’ ”

But she didn’t have to worry for much longer. The transfer took, something Rachel learned when she took a pregnancy test she’d ordered online.

“They make you wait 10 days for your blood test, but I had to know so I took a test and it came back positive,” Rachel says. “And then I was like, ‘Well, let me not say anything to John, just in case God forbid it’s a false positive.’ So I wait until I got the call and then surprised him with the happy news.”

John’s reaction was a little delayed, but only because of how Rachel shared the information. “I made a little box for John of a little baby’s outfit and I put the pregnancy test in there. But I put all of it inside of a Chanel box and I think he was mad at first when I gave it to him because he thought that I bought something for him at Chanel,” Rachel laughs. “He was kind of confused!”

That changed once it clicked. “Our girls were there and once he pulled out the pregnancy test he was like, ‘Oh my God, we’re having a baby!’ And there girls were so excited.”

Gianella and Giuliana, Rachel tells PEOPLE, have been asking “nonstop” for a sibling.

“The girls are over the top,” she says. “They’re talking to my belly like, ‘Hi, I’m your big sister!’ Gigi’s like, ‘Mommy, I’m going to be your little helper. Anything you need, I’ll help you.’ It’s really sweet to see. And Giuliana, she’s obsessed with babies. She’s asking if she can help change diapers, feed the baby bottles… she was like, ‘Mom, I’m going to carry the baby in the car seat.’ I’m like, ‘Oh, dear God…’ So this should be interesting.”

Jaiden, too, is looking forward to having another sibling. “He’s such a family kid,” Rachel says. “I know there’s a big age gap, but he loves to hang out with the kids; he and his girlfriend, they’ll actually come play with the kids for hours just to spend time with them. He loves being a big brother.”

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As for Rachel, though she’s been feeling all the usual pregnancy pains — like “painful” bloating and “crazy nausea” — she’s pushing through by embracing the happiness motherhood has brought to her life.

“There’s truly no better feeling in the world than having kids,” Rachel says. “It’s almost a type of love that you just can’t explain. Like, these little people make me a better person. They teach me every day. I’ve learned to slow down and just enjoy the small moments in life, like cuddling on the couch and reading a book together. And it keeps me grounded, because they remind me of what actually matters. They are my peace in this world amid the craziness.”

“I feel like my true purpose in life is being a mom,” she adds. “It fulfills me more than I ever thought possible. And I can’t wait to do it again. I mean, what’s better than to bring life into the world? How lucky am I?”

The Real Housewives of New Jersey is now streaming on Peacock.