The Duchess of Cambridge donned a pair of headphones and tried to interpret codes during her visit to Bletchley Park where her grandmother worked.
Valerie Glassborow worked as a civilian member of staff, probably as a duty officer, alongside her twin sister Mary.
Wearing an Alexander McQueen outfit, Kate greeted staff on a visit to mark a year-long restoration project at the Buckinghamshire site.
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Former prime minister Gordon Brown has paid tribute to Kofi Annan, who has died aged 80.
Both men were fatally injured in the smash, which happened at around midday.
A state funeral has been held for many of the dead in Genoa.