The triplets were delivered by Caesarean section at 31 weeks. Rocco was 3lb 5oz, Roman was 3lb 6oz and Rohan was 3lb 10oz.

They are the youngest of what is thought to be only a handful of naturally conceived sets of identical triplets in the UK.

‘I was surprised because I expected them to be non-identical,’ she said. ‘But then I’m normally the only one who can tell them apart, so that does explain a lot!’

Miss Allen, from Gateacre, Liverpool, who also has a three-year-old daughter, Indiana, had an early scan nine weeks into the pregnancy due to severe headaches and nausea – and was given the bombshell news she was expecting triplets.

‘I couldn’t believe it,’ she said. ‘I hadn’t even thought it might be twins, let along triplets, and we haven’t got any in the family.’

Doctors from Liverpool Women’s Hospital carried out weekly scans, and the triplets were delivered by caesarean section at 31 weeks. Rocco was 3lb 5oz, Roman was 3lb 6oz and Rohan was 3lb 10oz.

Now thriving at home, their personalities are starting to show through, their mother said.

‘Rohan is the loud one, he’s always shouting,’ she said. ‘Rocco is normally quite laid-back, but he can be feisty too, while Roman is usually complaining that he doesn’t want to share.

‘They’re always crawling about after the same toy, trying to get to it before their brothers do.

‘Indiana loves them, she’s not one bit jealous – I do feel a bit sorry for her when I think what it’s going to be like growing up with three little brothers though!’

The triplets get through around 130 nappies a week between them and four packs of baby wipes, while a pack of formula lasts about two days and the washing machine is run around three times a day.

As their father, Liam Tierney, 28, does not live with her, much of the day to day help comes from her sister Lauren, 17.

Before having Indiana, their mother’s ambition was to train as a neo-natal nurse – a wish she is even more keen to fulfil after what she has gone through.

Recalling hearing the triplet news, their mother said: ‘I couldn’t believe it. I hadn’t even thought it might be twins, let alone triplets, and we haven’t got any in the family'