As twins will often attest, it can be fun sharing important milestones with your womb-mate sibling. And some twins continue to share those milestones well into adulthood.
Fraternal 21-year-old twins Natalie and Leanne Paulson took their milestone-sharing to the next level when they became pregnant at the same time – then later gave birth to their babies just hours apart in the same hospital.
"It has been amazing to go through the pregnancy and birth with Natalie, as we have been able to share the whole experience together and get ready for the babies' arrival together," Leanne told TODAY.
"We have always been close from birth and have always done everything together ... we are more like best friends than sisters," said Natalie.
"We have both always been very maternal and wanted our own families, but never did we imagine we would share the experience of it all together and even have our babies hours apart."
Leanne went into labour on July 28, and remarkably, her sister soon followed, calling their mother the next day to tell her she was also on her way to hospital.
The sisters were admitted to the same hospital and given rooms next door to each other, with the pair meeting in the hallway to compare notes.
And when it came to the delivery, the sisters had astonishingly similar experiences.
"Our labours [were] exactly the same, the babies were both in the same position, and we both needed a little help during the pushing stage, as both babies' heart rates were dropping when we were contracting," explains Leanne.
The new mums loved sharing the experience.
"It has been amazing to go through the pregnancy and birth with Natalie, as we have been able to share the whole experience and get ready for the babies' arrival together. To go through this together has been surreal," says Leanne.
The experience has also been quite surreal for their mum, Denise Rawlings.
"I was flitting from one room to another [during the girls' labours] making sure they were both okay," she said.
"Although I was totally shattered after having no sleep, it was definitely worth it to have two perfect grandchildren who I adore."
Although newborns Carter and Mila-Rose were born just hours apart, the cousins have different birthdays, a point that delights their Grandma.
"I am happy that they were born a few hours apart and have separate birthdays," she says.
"Unlike my daughters, who shared a birthday, they can each have their own special day."