Tanguay, 41, says the techniques weren't widely known a decade ago when Jack was a baby, making it difficult to find decent swaddles and white noise CDs.
In 2006, after the birth of son No2, Tom, Tanguay took the plunge and launched The Sleep Store. She says the vision was to be a one-stop online shop for sleep solutions.
"Part of that is the products that we source and part of it is the free sleep information."
Sleep Store staff help soothe frazzled parents with free advice over the phone, by email or on Facebook, which Tanguay says has been a boon in allowing two-way, real-time conversations, and via the sleepstore.co.nz website, packed with articles on getting kids to sleep.
The store's original line-up of 20 products has now grown to more than 1000, encompassing all the stages of childhood.
This reflects her growing family - Jack and Tom are now 8 and 10 and have two younger brothers: Ben, 5, and Eddie, 3 - and the popularity of related products, such as baby carriers and feeding paraphernalia.
Continually evolving the range to meet the needs of bigger children has meant repeat business and loyal customers, who have been with them since inception.
Staff numbers have also grown. Husband Matt Anderson, 44, left his job at ACC a couple of years after the company's launch and several others have joined the workforce at the home-based headquarters in Titirangi.
An owner-operator course at Auckland business incubator The Icehouse opened the couple's eyes to the importance of adding expertise, rather than just more hands on deck, so last year they brought an accountant, designer and customer team leader on to the staff.
With the family income on the line they don't do anything too risky, says Tanguay, aiming instead for steady, organic growth.
She says being mindful that their customers are often on one income and price-sensitive means they have always worked to offer good value and products at a range of prices.
Providing top-notch customer service and smart delivery times has helped stave off competition from overseas retailers.
Auckland customers can often have purchases on their doorstep within 12 hours of ordering and Australian customers ordering off the local sister site wait only three days for delivery.
"Our customers are very driven by wanting their products quickly," says Tanguay.
This has meant year-on-year growth through periods when other retailers have found the business environment tough going.
"We've been alright because we've really stuck to our game plan and we've looked for growth opportunities as they've come along."
One such opportunity was when a valued supplier put her business on the market, offering the pair the chance to buy the Woolbabe sleeping bags manufacturer in 2011.
Woollen sleeping bags for infants have been an important sales category for The Sleep Store, and buying a key supplier was a significant milestone, giving them more control over the supply chain and product design.
It's not without its challenges, particularly with cashflow. Moving into manufacturing and wholesaling means facing big bills, says Anderson, and growing the Woolbabe range requires more investment.
The focus for the next few years is on the New Zealand and Australian markets. "We've thought about attempting to be a retailer further afield but we think at the moment our ability to provide really good customer service, we need to focus on Australia and New Zealand."
