Craig Allen Ruhstorfer donates blood at the Pingdu blood donation station in Shandong province.[Photo provided to China Daily]

At the end of last month, Craig Allen Ruhstorfer offered another 400 milliliters of blood, unpaid, to a donation service station in Pingdu, a county-level city in Shandong province.

The 59-year-old teacher and donor, born in the United States, is also known by his Chinese name Liu Tianxin, and has become a familiar face to the staff at the blood donation station.

"He has been offering blood donations at our station since 2007 and he has been awarded three blood donation certificates," said Dong Yongguang, a staff member at the Pingdu donation station.

Ruhstorfer has been donating blood, twice a year, since 2003 when he worked as an English teacher in the eastern coastal city of Qingdao. To date, he has donated 28 times or 11,200 ml of blood.

Not only is he an unpaid donor, but Ruhstorfer also provides funding for 22 Chinese children. This started after he met a child in 2003 whose family was in difficulties. He gave money for the child to go to school, and his good deed led to more contributions to help other children.

The eldest of the beneficiaries is now 25 and he invited Ruhstorfer to his wedding as a family member.

The youngest one is 9 and still in elementary school in Henan province.

"One of my 'daughters' has entered her junior year and one of my 'sons' has been admitted to the well-known Pingdu No 1 Senior High School this year," said Ruhstorfer cheerfully.

"And I hope all my children can attend universities and live happy lives."