She was working her typical overnight shift when a man knocked on the window around 1 a.m. Friday.
“He said she's laying on the ground about to have a baby,” Rehms said.
Rehms immediately jumped into action.
She grabbed towels and ran out to the grassy slope right outside the store.
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“The lady was laying right here, so I got the towels for her, this side,” she said.
Seconds later, the baby was out.
“She said she needed her pants off, so I took those off for her and I noticed the baby was crowning,” Rehms said. “So I asked her to lift her hips so I could put the towels underneath her hips, and as soon as she lifted her hips, the baby came right out.”
Paramedics showed up shortly after.
Video shows other strangers also stopped to help.
Rehms, a mother of two, said she relied on her instincts that morning and went into “mom mode.”
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“When you're a mom you kind of go back to those moments when your babies are born,” Rehms said. “There was no really fear. It was just mainly this needs to be done and she needs help.”
Rehms also said she broke store policy when she left the store to help.
"We're proud of Rashelle for her quick thinking and actions until additional help could arrive, and appreciate their quick response as well," a Starbucks spokesperson said in a statement to KIRO-TV.
Later that day, Rehms visited the mom at Tacoma General Hospital. She said mom and baby both appear to be doing well.
“It's an honor that I could be there,” Rehms said.
Rehms said she also hopes to stay in touch with the mom so she can get updates on the baby.