Christina Soosa was happy to be vaccinated against COVID, but the Perth mum wanted to "wait and see" before she signed her children up to get the jab.
She has since regretted that decision after her eldest son was hospitalised with coronavirus.
"My heart broke," Ms Soosa told Christine Layton on ABC Radio Perth.
"I just regret that I did not vaccinate them when it was available, and I put it off because of some safety things," she said.
Ms Soosa is urging other parents to vaccinate their children.
She said her sons fell ill not long after their school became an exposure site recently.
The first warning that her children may have been exposed to COVID-19 was an email from the principal of their school Westminster Primary, in Perth's inner northern suburbs, last Friday night.
"We were just shocked because we never expected it's going to come that soon to us," she said.
Fever, listlessness and loss of appetite
By Saturday morning her seven-year-old, who was already in isolation due to being a close contact, had a fever.
Ms Soosa said she suspected right away that he must have contracted the virus.
A PCR test confirmed her suspicions. On Sunday morning, her eldest son, aged 11, began to display symptoms.
As a youngster, he had a history of febrile convulsions — seizures brought on by a fever. Ms Soosa said his response to the virus was much more severe.
"My youngest one, his temperature went up to 38.5 degrees Celsius but still he was active … he was really responsive," Ms Soosa said.
"But when the temperature started spiking for my eldest son, he became very weak. He was just lying down on the sofa, not moving too much.
"He said: 'I'm very sick and weak' and he had no appetite."
By Monday, Ms Soosa became concerned enough to call an ambulance to take him to hospital, where he was found to have good vital signs but a high temperature.
She was relieved when he felt better after being given some ibuprofen and having a sleep.
Although no longer in hospital, on Wednesday Ms Soosa said the boys were still experiencing higher-than-normal temperatures.
One of the hardest things for Ms Soosa emotionally was keeping the children separated when the older boy was unwell and the younger was not.
"I will recommend every parent please vaccinate your child when you can, because if you're going to have one COVID case and you have four children in the house, that's when you have a dilemma," she said.
How to care for a sick child
Asha Bowen, program head of vaccines and infectious diseases at Telethon Kids Institute, and head of the Department of Infectious Diseases at Perth Children's Hospital said most children would experience COVID-19 as a mild illness that looks like a common cold.
A runny nose, cough, fever and sore throat were among the most common symptoms, along with gastro symptoms such as diarrhoea and vomiting.
"Then a large number of kids will still be asymptomatic, they'll be completely well, and yet may test positive," she said.
Professor Bowen said Western Australia had been lucky to have time to prepare for the virus' arrival.
She strongly encouraged parents to have their children tested if they were showing symptoms and to have them vaccinated as soon as possible.
If your child does contract COVID-19, Professor Bowen said there were some things parents could do to provide care.
"Watching your child closely and making sure that they're drinking as well as they can," she said.
"And if they do need panadol or nurofen for fever management, or for symptoms of pain or discomfort, then that's a really safe option to provide for kids at home."
She said Ms Soosa's experience of having children at home with COVID-19 was something families across WA could expect more often now that community transmission was increasing.
WA recorded 115 new local cases of COVID-19 on Wednesday.
