The New Jersey teen who took her own life two days after she was brutally beaten at school was a hero to a local mom after she saved her daughter from drowning.

Adriana Kuch rushed to the aid of the child in August, after she had swallowed water and started bobbing up and down in their backyard pool, according to the girl’s mom, who asked to be identified by her first name only, Roxanne.

At first, Adriana, who was nicknamed Sissy, thought the girl was playing.

“Then she realized no, something was wrong. She was so aware,” Roxanne said Saturday.

Video from the family’s security system showed Adriana throwing off her hoodie and jumping in the water to grab the eight-year-old triplet.

“Thank God you were here, Sissy!” Roxanne recalled telling her.

Adriana lived next door to the family and grew close to Roxanne’s children.

The mom said she couldn’t bear to tell her kids about Adriana’s death.

“I’m not telling the kids anything about this all because they loved her and they will go crazy. They will lose it,” the mom said.

Adriana took her own life on Feb. 3 in her Berkeley Township home hours after she received a message mocking her for getting her “a— whooped,” her father has said.

Four fellow students have been charged in the savage attack against her in their high school hallway on Feb. 1.

An obituary posted for the teen said she “adored all animals, she helped children with special needs, she loved jogging with her brothers and was a true nature lover. Adriana also enjoyed her walks in the woods, skateboarding, riding dune buggies and dirt bikes.”

If you are struggling with suicidal thoughts or are experiencing a mental health crisis and live in New York City, you can call 1-888-NYC-WELL for free and confidential crisis counseling. If you live outside the five boroughs, you can dial the 24/7 National Suicide Prevention hotline at 988 or go to SuicidePreventionLifeline.org.