In life, she was a charming toddler with an independent streak.

Now, after her tragic death in a swimming pool accident, Hanano Oyama has given hope to others as Singapore's youngest solid organ donor.

The 1 1/2-year-old's parents allowed doctors to remove her kidneys and heart valve after receiving the devastating news that she was brain-dead.

Her organs were then used to help other seriously ill patients, one of whom was a child. "The only thing keeping me going is that she has saved somebody's life," said her father, Japanese national Norimichi Oyama. "That's something I'm proud of."

Oyama recalled the moment he and his wife Kana, 35, a part-time administrative assistant, realised Hanano had gone missing two weeks ago during a family gathering at their Robertson Quay condominium.

The toddler was later found unconscious in the swimming pool. Doctors at KK Women's and Children's Hospital fought to save her, but she never woke up.

On Sunday, they broke the news to Oyama that she was brain-dead, and asked if he would allow her organs to be donated.

Despite his grief, he did not hesitate. "It didn't take me even one second to decide," the 33-year-old consultant told The Straits Times.

Doctors removed the organs in an operation yesterday morning. The recipients' identities have been kept confidential.

Solid organ donation involves the whole of the heart, liver or kidneys, as opposed to just tissues such as bone marrow and skin.

Oyama, who has lived in Singapore for two years and also has a four-year-old son, said he had been working with a transplant coordinator from the hospital since last Wednesday.

He described his daughter as charming and independent, with a strong character. She was well-loved by teachers at her childcare centre, who kept hugging and carrying her.

Oyama urged parents to be careful with toddlers near swimming pools, and donate their children's organs if they are intact.

Asked why he chose this step for his daughter, he said: "I made this decision, together with my wife, because I don't want any other parent to feel what I feel. If my daughter can save someone, then why not?"

In 2011, a three-year-old boy reportedly became Singapore's youngest solid organ donor after his parents gave consent for his kidneys and corneas to be removed.

The Health Ministry said there have been an average of one to two foreign deceased donors here every year since 2004, but this was the first case involving a child from Japan.