In a survey of more than 2,000 people, the girls' name chosen as the most likely to put a smile on people's faces was 'Emily' and the winner for the boys was 'George'.
Sadly, the boys' name least likely to make people smile was 'David' and 'June' for girls.
For the research, people were simply asked: "What is the name of a person who makes you smile the most?" and "What is the first name of the person who makes you smile the least?"
These were the results:
Boys' names most likely to make people smile:
Girls' names most likely to make people smile:
Boys' names least likely to make people smile:
Girls' names least likely to make people smile:
Dr Nigel Carter, CEO of the Oral Health Foundation, believes the names making people unhappy are doing so because they are associated with politicians.
"Politicians are rarely the most popular people but at such a politically charged time it seems that even the mention of some of our top politician names such as, David and Jeremy, is enough to swiftly banish our smiles," he said.
"Obviously this research is very subjective; we all have that one person in our lives that makes us grin from ear-to-ear and one which can quickly turn our smiles upside down."