Save for a family cost, but keep cash for a bad day. Use separate savings pots:...

https://www.bookmarking-base.win/planning-for-a-big-family-bill-this-uk-focused-guide-shows-how-separate

Save for a family cost, but keep cash for a bad day. Use separate savings pots: one for your goal, one for bills. Add a sum each month. Test it with an awkward month: less pay or a car fix