When + will (again!)

Hello,

I've just read the very interesting post on the possibility of putting "will" after "when". But I still have doubts in this peculiar case : I want to create a website about what will be the life in the 2040's, "when my baby is/will be 30".

Of course I don't want to make a mistake on a website address (how ridiculous!) and also, even if I know Paul McCartney's song "When I'm 64", it sounds weird to me without "will" because :

• "when my baby will be 30" stands alone (www.whenmybabywillbe30.com)
• and this website is all about future (actually the consequences of pollution and climate change in everyday's life)

So... I need help!

Many thanks in advance!