Advice on family planning

Hellooo AusHenry

Would love some advice on how we should approach the next phase of our life. We are looking to start a family in the next 3 years

29F and 28M - if we have kids knowing that I have to take mat leave as well

HHI 350k (250+100)

Own our property outright 620k - 2 bedroom apartment

Thinking of upgrading to a bigger home, but that would mean a property price of 1.8M

Should we upgrade or just keep investing our cash?

Editing with some additional info: - We can raise kids in our current place however that would limit is to one child ( or two up until 10 years old) - Everywhere (where'd we love to live) with 3+ bedrooms is sadly in the 1.8M - We'd prefer to keep our ppor and not sell it (sentimental first home) - Current investment portfolio, 140k in super, 50k in ETFs, 270k in vested RSUs