Aug. 29 (UPI) -- A zoo in England's minuscule pygmy marmoset monkey welcomed a pair of tiny twins on Sunday.
Chester Zoo shared video of Audrey the pygmy marmoset's two .53 ounce babies which just recently became large enough for visitors to see.
"Audrey's new twins are the tiniest of tiny arrivals!" Chester Zoo said.
The twins were born July 25, weighing a fraction of their mother's weight, and will only grow to be about 5 inches long.
"Pygmy marmosets actually have relatively large babies for their tiny size," Nick Davis, the zoo's deputy curator of mammals told ITV. "An adult will only weigh up to around 150 grams and so each baby equates to around 10 percent of its body weight."
The twins' father, Gumi, has assumed most of the parental duties while Audrey rests following the birth.
"After giving the babies their regular feeds, mum Audrey, like all other female Eastern pygmy marmosets, steps aside while dad takes on the parental chores," Davis said. "The youngsters can therefore often be seen being carried by dad Gumi for long periods of time as mum takes a well-deserved break."
*15g babies! 😍*— Chester Zoo (@chesterzoo) August 28, 2017
Pygmy marmosets are the smallest species of monkey in the 🌍.
Audrey's NEW twins are the tiniest of tiny arrivals! pic.twitter.com/QBKUP5EjXH