They were separated at birth — but not for long.

A little after 7 a.m. Friday, a firefighter — who had given birth not that long ago herself — delivered a baby girl in 20-degree weather on Interstate 270 in Rockville.

Many news outlets — including this one — ran with a heartwarming story that ended with mom and a healthy child on their way to a warm hospital.

But the real end of the story was that the mom delivered another baby once she got there.

Katie Weaver, the Montgomery County firefighter who delivered twin No. 1, said two ambulances arrived after the roadside birth, one for the baby and one for the mom, who was getting ready to deliver baby No. 2.

The mom’s ambulance made it to the hospital in time.

But that first birth was fast. Weaver, who usually drives a fire truck, said she had about 30 seconds before the child’s arrival.

“I looked in the front seat, and she was having a baby,” Weaver said. “Enough time to walk up to her and ask her a few questions, and then she started having a contraction and — there was a baby.”

Weaver, the mother of a 3-year-old and a 1-year-old, said she has helped deliver three or four babies in the county.

“Along the highway is not ideal for a delivery,” she said. “But everything went really well, given the circumstances we were dealing with.”