Can you talk to me in English?

My five year old is worried about his English. Today in the car:

'Mum, can you talk to me in English?' 'I'm afraid I'll forget my English when we go to school in Australia'.

We've been in Holland now for three weeks. Three weeks ago his sentences consisted of 60% Dutch and 40% English. Now it's 95% Dutch and 5% English. Young children can switch so easily.

I explained to Sebastiaan that he'll remember his English as soon as we arrive in Sydney. He then asked if we could wait sending him to school until he thinks his English is good enough. So cute.