A shocked waitress has described how she was left in tears after a generous diner overheard her talking about how much she missed her son and left her a whopping $200 (£130) tip so she could go and visit him.

The random act of kindness was even more surprising to the woman known only as Brandi because the unknown patron of the US-based restaurant had only spent $9.34 on their meal.

Images of the till receipt showing the tip received and an accompanying handwritten note were posted on image sharing website Igmur.

Thoughtful: Waitress Brandi was reduced to tears after an unidentified diner left a huge $200 tip on a bill that came to just $9.53 after hearing her talk about how much she missed her son

The feelgood story has since been shared around the internet.

The satisfied diner wrote on the back of the restaurant bill: 'Brandi, Thank you for your service.

'I overheard you talking about your son. Use this and visit him.'

The till receipt clearly shows the visa transaction has a $200 gratuity added.

The waitress, known only as Brandi, was so taken aback by the gesture that she was reduced to tears.

She said: ‘I completely broke down in the kitchen when the host brought this to show me. Kind and caring people do still exist’.

The identity of the kindly tipper remains unknown.