Lance Bass and Husband Michael Turchin Welcome Twin Babies Violet and Alexander via Surrogate

Lance Bass is a dad times two!

The *NSYNC alum and husband Michael Turchin welcomed their first children, twins Violet Betty and Alexander James, via surrogate on Oct. 13, he announced on Instagram Thursday.

Jeff Kravitz/getty Michael Turchin and Lance Bass

Violet was born at 17.5 inches long, weighing 4 lbs., 11 oz., while her brother was born at 18.5 inches long, weighing 4 lbs., 14 oz. Alexander was born one minute before his twin sis, at 1:24 p.m. on Wednesday.

Bass, 42, shared the exciting news alongside photos of the twins' birth certificates, which included stamps of their tiny footprints.

"The baby dragons have arrived!! ??????????" Bass wrote in the caption. "I can not express how much love I feel right now. Thank you for all the kind wishes. It meant a lot. Now, how do you change a diaper??! Ahhhhhhhh!"

RELATED: Lance Bass Says Twin Babies on the Way 'Could Come Any Day' Now: 'I'm Kind of Really Scared'

Earlier this summer, Bass revealed the baby news exclusively with PEOPLE, saying it had been "quite the journey" as he opened up about years of surrogacy attempts, failed IVF treatments and a miscarriage.

"We always knew we wanted at least two kids," he said at the time. "It would be nice to have a boy and a girl just to feel the experiences of raising both or whatever they end up being. I think it's just amazing that science has gotten this far where we can make the healthiest human beings ever. And I hope in our lifetime, we'll be able to see the whole world be able to do this."

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Courtesy of Lance Bass Lance Bass and Michael Turchin

Bass also shared that they are due "in early November," though he said, "But I need them to get here before Halloween, because I need them to be Halloween babies. They have no choice but to love Halloween because I'm obsessed and they're going to be obsessed."

Turchin, 34, told PEOPLE at the time that he's most looking forward to watching their kids develop a strong sibling bond.

"Just the fact that they'll, I mean hopefully, like each other. I like my sister, we were best friends and that was the cool part growing up — I always had a best friend with me all the time," he said. "I was never bored. That connection is super rare to have with a sibling when you're that close. It's just a really special relationship and I'm excited to see that play out with our kids."