My other half has a far better paid job than I do, but then her employer was happy for her to work part-time when she returned to work. Mine although very accommodating wanted me to work the same hours. It is a little more flexible, so the 3 nursery days I work 8-4 and the other 2 days 8-5.30. I've cut my usual hour lunchtimes for the week down to half hour, so I generally work till 5:30 the 2 full days so I'm doing the same hours as before to keep my wage unchanged (40 hour week)... Laura changed from 8.30-5 for the week to 9-5.30 for her 3 days. Means she can do the nursery drop off and I can do pickups. She's also paid for 4 hours on a saturday morning worked as a rota (2 weeks in 3 for a 28 hour week), It also dropped her down several tax brackets so she's taking home a little more than we had initially thought. After childcare and mortgage we probably have ~£500-600 'left over' each month. Throw in the weekly shop, DD bills, fuel etc into that and it's closer to £200-300 to 'live on'. So let's just say cycling our commutes is a must and we don't go out very often, or when we do it's on a voucher...!
Thankfully I have a bunch of savings. When we re-fixed our mortgage there was no benefit for paying a chunk of it off, so some of that money went into monthly payments into an ISA. Things like that really help out - it 'earnt' me £200 over a 12 month period, far more than any interest. I also have some rental income from property which helps as a yearly injection - it just about covers the council tax for 12 months and the car insurance (it's not much), but is a massive help. It's those big bills which really hit the savings otherwise. On the flip of that, the fact I have income from co-owned property and we have savings, means we get zero benefits.
When we setup our mortgage we basically made sure that the one of us who got paid the least (me) could still afford it if the other one lost their job - while also giving us the bare minimum to live on. That was before the little one but it's certainly helped as means we're not in debt coming into parenthood like many other families. Also Laura only having the 8 months maternity, hear of so many rolling it up to 12 months (4 of those being unpaid!) The years before we had lots of disposable income which we where both quite good at saving. That's the 'buffer' we have now. We sat down and 'worst case' scenario'd it. The worst was a shortfall of £6k a year until we got free childcare so we made sure we had the savings to cover those 3 years if we really needed to. We haven't, so the times we dip into the savings for things we have been generally able to pay back the next couple of months. A real buffer! We have friends who've had to take out loans to cover such things. Getting into crazy amounts of debt with no hope of paying it back for 3+ years!
Too many bundys! 
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