But when her husband Jeff Green came home from a dinner engagement soon after and went upstairs to change, he discovered Hudson had been up to the proverbial "no good."
The toddler was in the bathroom, a bottle of children's acetaminophen and another of an antihistamine-decongestant beside him on the floor.
Both were empty.
"We freaked out," said Esteves, recounting how her son had gone into the bathroom of their Toronto home, pulled over a stool and climbed up on a shelf to reach a bin where she kept the medications, a good metre and a half off the floor.
"So the little scamp got in there and he was able to open the child-resistant caps, no problem," she said. "He showed us several times how he closed them and opened them again.
"And it happened so fast. The difference between 'night-night' and Jeff going upstairs was 25 minutes. Luckily he came home very early."
While Hudson fortunately suffered no ill-effects from his foray into the medicine box, the incident is cautionary tale for parents about how quickly a determined child can get into substances that might do them harm.
Indeed, poison centres across Canada field about 160,000 calls a year about children who have been exposed to medications, cleaning supplies, household chemicals or health and beauty products — almost half of them involving kids under six years old.
"When you think about child development, that's when they're getting curious, they put everything they find in their mouth," said Pam Fuselli, executive director of Safe Kids Canada. "That's how they explore their environment. They're learning to walk and climb and trying to reach new things and new places where they haven't been before.
"So that is probably one of the key reasons this group is at risk."
Each year in Canada, an average of seven children under 14 die and about 1,700 end up in hospital with serious injuries as a result of poisoning.
"From the phone calls every year, we're still seeing huge numbers of kids being exposed and unintentionally getting into poisonous products in their homes," Fuselli said.
A recent poll by Leger Marketing commissioned by Safe Kids Canada found 98 per cent of parents with children under 14 believe it's important to lock up medicines and household products. Yet half conceded they store medications in a medicine cabinet and more than 60 per cent said they keep cleaning products under a sink.
"I think some people may think the child-resistant caps on medications will keep kids out of the product," said Fuselli. "Unfortunately, they're not child-proof. They're only child-resistant and children are very curious and they can actually get those caps off, given enough time to get into them."
Dr. Margaret Thompson, medical director of the Ontario Poison Centre, said cleaners like bleach, detergents and disinfectants — items often found under the kitchen and bathroom sinks — topped last year's list of toxic substances children were exposed to.
Not all kids ingested them: some splashed a product on their skin or in their eyes, leading to burns and other harmful effects.
Pain medications were the Number 2 most common cause for calls to poison centres, she said, followed by personal care products like deodorant, toothpaste and perfumes.
Foreign bodies, such as tiny building-block pieces, and vitamins rounded out the top five.
Young kids can be particularly attracted to children's medications, including analgesics like acetaminophen and ibuprofen, Thompson said.
"A number of the medications that are formulated for children, the manufacturers are trying to get children to tolerate them, so they add a flavouring to them to make them more attractive to make them finish the appropriate dose," she said.
"It tastes like grape or bubble-gum, so they desire that sweet flavour."
Fuselli said parents should never call medicines or vitamins "candy."
"If you refer to it as candy to try to get them to take it, they will not be able to distinguish between true candy and the medication and they may take it themselves while you're not around," she said. "And don't take medication in front of kids — they may seek to imitate you."
Thompson said many incidents occur when a parent has either taken a dose of their own medication or given the child theirs, then turned their back for a few minutes.
"That's when most of these things happen, just after they've been used," she said. "That's the critical time. It's not that kids go climbing up into a cupboard — some of them do — but the majority are when the parent inadvertently left it on the counter and may have forgotten to put the top back on or may have forgotten to lock it back up again."
Thompson said medications, cleaners or products like antifreeze should never be taken out of their original containers and put in "something more convenient."
"Because then we lose the label," she said of poison centre staff or emergency room doctors. "We don't know if there's a poison symbol or a caustic symbol. We don't know the concentration of the product. We don't know maybe what the real product is and we lose the child-resistant cap.
"So Grandma who comes to visit with a baggie full of her medications for the weekend has taken them all out of their original containers and we have no idea what Grandma's medications are then."
Some other tips to make your home a poison-proof zone:
—Buy medications with a child-resistant cap whenever possible and store all medications and vitamins in a locked box. Keep the box and key out of sight and reach of children.
—Store household cleaners, like dishwasher detergent and bleach; car supplies, such as windshield washer fluid; cosmetics, like nail polish remover; and garden supplies like pesticides, in locked bins, cupboards or drawers. A child safety latch is an acceptable alternative.
—If you suspect your child has been poisoned, call your local poison centre or 911. Add the number of your area poison centre to your cell and home phones. Numbers can be found at: http://napra.ca/Content_Files/Files/Canadian_Poison_Control_Centres.pdf.
While Esteves said she and her husband were careful before the scare with Hudson, they have since become even more vigilant.
"We've changed things in the house a little in that medications are even higher and in a box now that they can't access," she said, offering this advice to other parents:
"Understand what your children are capable of, if they are climbers, if they sneak things from the cupboard. Just thinking beyond that to what else they might be likely to access. And then ensuring that those things are where they should be, that they're locked up tight."