The 37-year-old paid an early morning visit to their home in Upper Drive, Hove, and left a ram munching on their lawn.
His mother Breda said: "I woke up and went down stairs to make a cuppa and as I was filling the kettle I gazed sleepily out the window and saw a huge ram staring back at me.
"At first I thought it was a massive ornament but then I saw it blink and realised it was alive."
Breda and her husband Frank instantly knew the culprit must be their son.
They discovered a letter posted through their door which read 'Tinker or Tailor, weasel or stout, on All Fool's Day - is it a sheep...or is it a goat?'.
Breda said: "We can't believe he managed to do all this without waking us up. He even dragged our garden seat from the front lawn to the back so he could tie the animal to it.
"Frank went out a gave the ram a pat. He was very friendly and seemed very happy chomping away on a pile of hay. And our grass of course!"
Aiden said: "They are very proud of their lawn so I thought I would get them a sheep to keep the grass nice and short."
Aiden borrowed the prize winning Jacob's ram from his friend Roger Bailey, a farmer near Lewes.
STEVE Rump decided to enter into the spirit of April Fool's Day and have his head shaved for charity.
The 33-year-old Homebase warehouse manager, of Broyle Close, Ringmer, volunteered to raise cash by allowing wife Carol to shave off his locks.
Converted for the new archive on 30 June 2000. Some images and formatting may have been lost in the conversion.
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