Catherine Phinney’s face flooded with a mother’s love Thursday on the stand when she looked at a photograph of her 20-year-old daughter, ­Janet, who was strangled and dumped into the woods behind the family’s West Roxbury home 25 years ago.

“Oh, she looks mad,’’ ­Phinney told a prosecutor in a gentle moment describing a photo of her daughter when she was alive during a Suffolk Superior Court murder trial in which jurors had already seen photos of Janet Phinney’s brutalized body.