It is understood the Mortimer ran her own business, Sweet Beginnings, offering bespoke bridal gowns and wedding planning services.
A wedding photographer based in Gloucestershire, who did not wish to be named, said: "Laura was a lovely lady with a kind word for everyone.
"An inspiration to many people, not only personally but in the wedding industry too.
"She worked so hard to get where she did and was extremely well respected throughout Gloucestershire and beyond.
"I know every Sweet Beginnings bride and wedding supplier is thinking of her and her family."
Detectives and forensics specialists erected a white tent by the property, and the quiet cul-de-sac was cordoned off for most of the day.
Neighbour April McMillan, 23, said: "I woke up hearing a loud bang.
"I didn't think anything of it because we've had roadworks around here and there's been lots of bangs but this one was on its own.
"There are lots of police about. It's very shocking, I can't believe it."
A kilometre along the river Severn, a large area of the Westgate Boating Lake and Recreation area was also cordoned off by police.
A local man interviewed there said officers had told him they were guarding the scene of the arrest.
He said: "They told me they stopped him on the Westgate Bridge. He could have gone into the river or onto the rail track from that bridge."
"A 28-year-old man was later arrested on suspicion of the murder of the woman and the girl. He is still being questioned by officers," a police spokesman said.
"Forensic inquiries will be continuing and post-mortem examinations are due to take place in the coming days.
"The family of the victims has asked for privacy at this time. We would like to thank the local community for their patience and assistance today.
"Multi-agency meetings will be held over the coming days, with the aim of providing support to our communities, particularly young people."