The 19-year-old, who is a member of Britain’s biggest family, delivered her daughter Ophelia last week.
So far the teen, from Morecambe, Lancashire, is taking parenting in her stride and not struggling with sleep in the slightest.
In a video of her baby’s first photoshoot, she can be heard saying ‘all she does is sleep’.
Millie’s mum, Sue, 45, who has 21 other children with husband Noel, was with her daughter at the shoot at Jade Davies Newborn Studio.
The 19-year-old had been eagerly looking forward to the occasion, saying ‘it’s all I’ve been thinking about’.
Sue previously took her youngest daughter Heidie for a session at the studio.
Ophelia weighed 7lbs and 12oz when she was delivered last Thursday.
Millie revealed the details of her traumatic labour after she was rushed into theatre due to birthing complications.
She described how her cute little tot came out “kickboxing” with her fists up.
In a video posted to YouTube, Sue said her daughter did “brilliantly” during the difficult birth.
“Millie managed on gas and air. She came in at six centimeters, and you did brilliantly, didn’t you,” said Sue, 45.
“I can’t believe you came in at six centimetres, and she was born five hours later.”
Before Ophelia was weighed, mum and grandmother took turns guessing what she might be, with Sue only an ounce out with 7lbs 13oz.
She said her granddaughter was tiny but had “massive feet”, adding the baby was not in an ideal position as she came out, with Millie suggesting that’s probably why the birth took as long as it did.
Her daughter suffered a “secondary degree tear”, with the mum looking after Ophelia while Millie was in theatre for around two hours.
However, because Millie “spiked a temperature and Ophelia pooed inside Millie just before she was born” doctors wanted to keep her in for 24 hours to check neither had an infection.