"Our first child surprised us, so we weren't prepared for it," says Molly, 30, a financial adviser from Essex.
Molly and Taylor, who's a train driver, were earning similar amounts, but once Molly spent more time at home with their baby, the balance changed.
"Taylor's career propelled and mine took a step back," she says. "There's an unintended impact on the person who spends more time at home with the kids. "
One of the things the couple decided to do was have Taylor contribute to Molly's pension while she was off work.
"We were looking after both our futures, not just Taylor's," Molly says.
It is something she thinks far more couples should discuss before having children.
A partner can make what is known as a third-party pension contribution. For someone with no or low earnings, up to £2,880 can be paid in each tax year, with basic-rate tax relief increasing that to £3,600.
For someone still earning, their partner can also contribute, subject to the recipient's pension limits.
Katie Guild, co-founder of financial community Nugget Savings, says the pension gap can begin during maternity leave because an employee's own contributions can fall as their pay drops, and contributions may stop altogether during periods of unpaid leave.
She says couples should consider whether the partner continuing to work could help make up some of that shortfall.
Before having a baby, she recommends working through a few key questions:
Molly and Taylor now have two children, aged two and five, and say they were much more prepared the second time around and stopped thinking about household costs as something that always needed to be divided exactly in half.
The couple, who each earn around £60,000, have their own bank accounts alongside a joint account for bills, but are flexible with the amount each contributes when their circumstances change.
During Molly's maternity leave, for example, they adjusted the split and she's found it helpful to "view finances as a household".
The couple say they are teaching their children about money from an early age.
They set pensions up for both kids when they were born and have been paying into them through a monthly direct debit.
Molly explains: "It's like a gift for the future as they can't touch that money until they're in their 60s and we won't be there to see that. "
They also use Junior ISAs, although Molly points out that once the children are old enough, the money becomes theirs to spend "and if they want to, they can take that money and blow it in Ibiza".
Taylor says their five-year-old is given small jobs to earn a couple of pounds, rather than simply being bought everything she asks for.
They are also beginning to introduce the idea of saving by telling her that she can spend a pound now or hold on to it and potentially have more later.
Guild says couples should check what support they can receive, including , external and , external.
She adds that conversations about money should not stop once parental leave begins and when the baby arrives she advises couples should:
