A SHOPPER wants to trace a mystery member of the public who came to her aid when her young son suffered a fit so she can say a proper thank you.

Sarah Johnson was out shopping in Chesham with two-year-old William on Saturday when he suffered a febrile convulsion - a seizure which caused him to lose consciousness and for his limbs to go stiff.

Another shopper came to tend to William while an ambulance team made its way to the scene.

But Mrs Johnson didn't get chance to say a proper thank you to the woman who gave her family a helping hand.

She's now trying to find her so she can express her gratitude in person.

She said: "I don't remember too much of what she looked like and I don't know who she is.

"I was very touched by the way she was so calm. She was just a member of the public who took the time to help us out. A lot of people would stand and watch and be concerned but wouldn't want to be involved.

"If she got to see how appreciative we were, that would please me."

Mrs Johnson added: "We rushed into Boots, which was the nearest store, and went to the back where the pharmacy was.

"I grabbed a member of staff, who phoned for an ambulance. This lady, who was a customer at the pharmacy counter, come along to us and said, 'We need to turn him on his side', which she helped us do.

"She reassured my husband and I, watching William very closely and reassuring us the whole time until the paramedics came. Although we weren't calm, it was nice to have somebody there who was calm.

"I said a very quick thank you. I grabbed his pushchair and rushed out the door - there was no hanging around."

William had to stay in hospital for 48 hours after his ordeal but is now back at home in Tring.

Were you the shopper who came to help William? Contact our newsdesk on 01494 755084 or acarswell@london.newsquest.co.uk.