I'm thinking of keeping costs down a bit and sticking with a more modest skoda octavia vrs.

They are currently phasing out the old model so have a good deal on it at the minute, 0% Apr and 2000 deposit contribution

Back in November we looked at the Octavia but we decided on a Superb.

There were several good reasons to get the Superb but the main one was quite simple. Even in November it was dealer or central stock only and despite only wanting a relatively modest model there were none that met our spec anywhere. Move on 2 months and those stocks will be further depleted so you choice will be severely depleted and you may find yourself having to have many expensive and unesessery extras simply because all the value spec cars have gone and the PCP will be much higher.

Just because they are advertising them does not mean they exist.

Your Polo GTI has done remarkably well (assuming it's a 3-year PCP) to have only £300 negative equity after less than 2 years: clearly a good choice in the first place. You could have a bit of positive equity in it nearer the end of the contract, but bearing in mind what SLO76 says (and he's in the car business), there probably won't be much in it.

The Octavia vRS will be a good choice, particularly the petrol version: either the hatch or the estate will be far more roomy than your other two choices. New parents are always surprised by how much stuff a baby needs when travelling.

Maybe see if there's a good deal on a car currently in stock (the dealer will look for you at what's is the system) and go for it is so: if not don't despair too much as a facelifted model will hold its value better.