The Duke of Cambridge joked about spending his first night away from baby son Prince George who he described as having a "voice to match any lion's roar".
William and wife Kate were guests of honour at the inaugural Tusk Trust awards, held at the Royal Society in central London, which recognised the work of campaigners.
In a speech to guest, William said: "As you might have gathered, Catherine and I have recently become proud parents - of a baby who has a voice to match any lion's roar.
"This is actually our first evening out without him, so please excuse us if you see us nervously casting cheeky glances at our mobile phones to check all is well back home."
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