Milly had already formed a particularly close bond with Mrs Horscroft's 8-year-old son, Jason.
There had been no problems with the adoption, and Mrs Horscroft encouraged others wanting a pet to consider the SPCA.
"She was shy at first .. she had been at the SPCA for such a long time, but she eventually snapped out of it."
The SPCA gets inundated with unwanted animals over the Christmas period, stretching its resources.
"So finding homes and suitable homes is very important to us," said executive director Bob Kerridge.
He said adoptions at the SPCA had improved over the past few weeks.
"We are very appreciative to the Herald for their assistance in that matter.
"It's fair to say we also had a lot of requests for driving dogs and a lot of people are asking what the cats can do."
Mr Kerridge said getting animals adopted over summer was vital as there was always a huge influx.
Some are unwanted Christmas gifts which were exciting for a day before interest waned.
"Some people, when they go away for a holiday, find it cheaper or easier to just drop their pet into us rather than have someone take care of it."
Summer was also kitten season as many people neglected to have their cat spayed.
Mr Kerridge said he was constantly amazed by how resilient the animals were that came to them. "They're just young, innocent kittens that are really just lost and don't know much. From that point of view, it's vital that the types of homes that we find are going to be homes that are going to care for them for the rest of their lives.
"And that's what we stress to people - these are animals that are only needing one thing, and that's your love."