The ‘False Widow’ spider found in the hand of a 15-month old, Ava Shephard. See MASONS story MNSPIDER. A mother was terrified when she found her baby holding one of Britain’s most poisonous spiders. Sadie Perry, 27, saw 15-month-old daughter Ava Shephard drop a bug on the carpet so she took a picture. It was only after she posted it on Facebook pals told her it was a false widow. Wildlife expert Owen Leyshon confirmed he is “99% sure” the spider spotted by Miss Perry is one of the genus of Steatoda, commonly known as the false widow. Although not naturally aggressive towards humans, its fangs are capable of piercing flesh and the venom can cause a painful swelling.