When Jane Archer found out she was pregnant, her family knew that she would give birth on the same day as Kate, even though she didn’t.

Jane, from Dagenham Road, Rush Green, said: “They were egging me on and said that I was going to give birth on the same day as Kate.

“They kept on saying that I was competing with Kate.”

They clearly knew something she didn’t, because her first son not only arrived on the same day as the future king, but came in just three minutes after the royal baby.

The baby seemed determined to share his birthday with Kate and Will’s baby, even though Jane didn’t know it.

He arrived six days early.

Jane, 42, said: “I didn’t think that there was any chance of me giving birth on the same day.

“My two daughters came late, so I thought that this one was going to be the same, but he obviously had other plans.”

The labour couldn’t have been more straight forward.

She gave birth less than 45 minutes after her waters broke.

She said: “It was so easy and Queen’s were brilliant.

“It was a water birth and it was very relaxing.”

Jane’s baby might not be a royal, but he is extra special to her because she was told that she couldn’t have anymore children after the birth of her second daughter, 15 years ago.

“He was a big surprise, said Jane.

“I was doing a mountain climb in North Wales with my partner, when it first crossed my mind that I might be pregnant.

“I remember that I couldn’t get to the top of the mountain and I was just feeling really sick.”

She added: “As soon as I came down, I did a pregnancy test and I was so surprised when it came up positive.”

There does seem to be some downside to sharing your birthday with the future king.

Jane is waiting for Kate to name her baby before she decides on the name for her son.

“We want to call him James, but I think Kate will also go for the same name.

“If they decide on James, then we will go for Henry.”