Kerry, who was in the labour room when her daughter Leighanna gave birth to daughter Hermione, said: "It was so emotional. My own experiences of labour came flooding back. Hermione looked very much like Ben with tufts of dark hair just like his.
"If Ben was here then he would probably be one of the first people to see her when she came home. You do think about things like what card would he have got her and what would he have bought her?"
"Our lives very much revolve around keeping the search going for Ben and the campaign, so Hermione coming along is a blessing. Something positive to focus on.
"I don't think it would have made it any harder if she'd been a boy and I don't think it makes it any easier to deal with that she's a girl. We've just got to cherish that Hermione is here.
"She's an absolute princess and is going to be spoilt that's for sure."
Kerry's son Ben – Leighanna's brother – mysteriously vanished on a Greek island when he was 21 months old and Kerry, now 42, was only 19.
In an interview with the Mirror, Leighanna said: "We've already compared her baby photos to Ben's and they are the double of each other. Hermione looks very much like me and I looked very much like Ben.
"We were all so happy but Ben should have been there too to dote on his first niece. It would just make everything perfect and complete.
"But I will never give up hope that one day we will find him and he will part of our family again."
Leighanna was training to be an accountant last year when she found out she was pregnant by her partner of five years, window fitter Craig, 24.
They had just come back from a holiday in Turkey at the time. It was unexpected news because Leighanna had been diagnosed with Polycystic Ovary Syndrome when she was 14 years old and doctors predicted she would struggle to conceive.
She said: "I was in a state on shock initially. We had never planned on having a baby so young but as the news sunk in we were delighted."
Kerry added: "It was a huge shock when Leighanna told me she was pregnant because she was very much career-motivated at the time.
"She did say she would like children but later on. She wanted to get her career in order. So for her to find herself pregnant was like, 'Oh my god'.
"But I think she was older than I was when I got pregnant with Ben. The fact she's young means she will be like me. Leighanna and I are very close –it's like a sister relationship and a mum relationship. She will have that with Hermione which I think is a good thing."
Both Kerry and Craig were at Leighanna's side when Hermione was born weighing a healthy 6lbs at the Jessop Maternity Unit in Sheffield.
Kerry recalls: "Leighanna coped really well with the labour. It was very emotional and a very happy time. My mum was allowed to come in the last half an hour too so there were four generations of Needhams there."
Leighanna said her daughter will grow up knowing who her uncle is.
She said: "There are pictures of him all over the house and when she is old enough I will explain to her in the kindest way I can what happened to Ben.
"If he still hasn't been found, and she wants to be involved in the search for him, that's fine. But I won't push it on her.
"More than anything, I just wish he was here to share this very magical time and enjoy watching Hermione grow."