The former Good Morning America host's daughter Jamie Krauss Hess welcomed son Mason on Wednesday

By peoplestaff225
Updated September 15, 2015 10:30 AM

The Lunden family keeps expanding!

Joan Lunden‘s eldest daughter, Jamie Krauss Hess, gave birth to a son on Wednesday, Sept. 9, a rep confirms to PEOPLE.

Born in Connecticut weighing in at 8 lbs., 2 oz. and measuring 20¼ inches long, the arrival of Mason Levi Hess made the former Good Morning America host a grandma for the second time.

“We were getting text updates all night long, waiting for baby boy Hess to come and finally at around 4:30 a.m. it was time,” Jamie’s sister, Lindsay Krauss Weinberg, tells PEOPLE.

“We raced over to the hospital and met little Mason and he was perfect! We couldn’t take our eyes off of him, a new little life added to our family.”

Joan Lunden daughter Jamie grandson Mason Levi

And Lunden, 64, who goes by “Jo-Jo” instead of grandma, couldn’t be more thrilled.

“She couldn’t take her eyes off him,” says Lindsay. “She kept saying, ‘My first baby has a baby!’ ”

In addition to her new grandson, Lunden has a granddaughter Parker, 1, and is mom to three daughters from a previous marriage: Jamie, 35, Lindsay, 32, and Sarah, 28.

She and her husband Jeff Konisberg, 54, also have two sets of twins, Kate and Max, 12, and Kim and Jack, 10, born via surrogate.

— Emily Strohm