The pretty star of the ITVBe show - who's been engaged to fiancé Greg Shepherd since February 2014 - was planning to be pregnant by Christmas and married by next September, but admits work got in the way.
Billie, 25, has just released a clothing range with In The Style UK and is juggling that with filming for TOWIE, running her Essex clothing boutique Minnies and being mum to 16-month-old daughter, Nelly.
"I've always said I want two kids really close together in age, so I originally wanted to be pregnant by Christmas, but I've got so much going on at the minute that it might end up being the beginning of next year," she says.
"We're looking at 2017 for our wedding now, we've moved everything back a little bit. So another baby in 2016 and then a wedding the following year. I'm just so busy at the minute."
She adds: "It can be quite challenging juggling being a mum with work and everything else.
"I don't have a full time nanny or childcare, so my mum helps me out a lot. I don't know how we get through it sometimes, but we manage – we juggle it! It can be quite stressful."
Billie met Greg on a holiday to Ibiza with her sister Sam, 24, and admits they've been "inseparable" ever since their first date.
"He's a total romantic," she says. "He always plans nice things for me and takes me to places I want to go. He'll book a night in a nice hotel and he buys me sweet little gifts."
She adds: "He's a great dad too – in the beginning I didn't think he was going to be that hands on, but he's really helpful.
"He bathes her, makes the bottles and he just has fun with her."
"I'd hate to constantly be picked to pieces over my relationship," she says. "I think Greg not being on TOWIE has massively helped us. It's great we've both got our own things going on and don't work and live together.
"He's different to the TOWIE guys, he gets on with them all, but he's a bit older and more mature. He's had all his years of partying and has got other responsibilities now."
Billie's gorgeous Christmas clothing collection is available from www.inthestyle.com
To read Billie's plans to help sister Sam give birth, pick up a copy of Reveal magazine - OUT NOW!
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