And when compared to a snap of Kate Middleton at the same age, the young royal is the spitting image of his mum.
It turns out Kate has quite an eye for photography!
It's not the first time that Kate has taken pictures of her children to mark their birthdays. A white collared shirt with blue trim just pokes out from beneath his sweater.
Prince George pictured in the arms of his mother on November 2, 2014.
The prince is expected to have a new cousin in the coming weeks, after the Duchess of Sussex revealed she is due to give birth at the end of April or start of May.
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She said 20 persons have so far been rescued from the collapsed supermarket and brought to the nearest hospital. "Our rescuers are telling us there are people in there shouting, begging to be rescued".
Louis is seen smiling in all three of the photos, with his two bottom teeth showing.
In 2018, Kate went into labour in the early hours of Monday morning (23 April).
Prince William was by the Duchess of Cambridge's side to welcome their third child in the Lindo Wing of the Paddington hospital. (REX/Shutterstock) Prince Louis looks the spitting image of his brother Prince George.
Ahead of Prince Louis of Cambridge's big day, Prince William and Catherine, Duchess of Cambridge shared a series of unseen photographs of their youngest child via the Kensington Royal Instagram page.