‘Doogie Howser, M.D.’: Max Casella Was 5 Years Older Than His On-Screen Character

The acting world is full of little quirks, and one that has caught many fans off guard is learning about the real-life ages of actors who play children on screen. Working with child actors can be difficult. Between labor laws, juggling school schedules, and having to deal with rapidly-changing appearances during growth spurts and puberty, it can often be easier to get a young adult to play a teenager

The end result, though, means that often there is a mix of actual teenagers and much-older co-stars working alongside one another as if they are same-age peers. Some TV shows have cast actors in such a way that the age differences are stunning when they come to light.

Twenty-nine-year-old Jason Earles played a 16-year-old on Hannah Montana alongside actual teen stars. Keiko Agena was 27 years old when she portrayed the 15-year-old Lane on Gilmore Girls — despite being cast alongside much younger Alexis Bledel.

Doogie Howser, M.D. is another series that had a substantial age gap for one of its characters. 

‘Doogie Howser, M.D.’ premiered in 1989

RELATED: ‘Doogie Howser, M.D.’: Neil Patrick Harris Wasn’t the Network’s Favorite Casting

Doogie Howser, M.D. is best remembered as the show that launched a young Neil Patrick Harris into stardom. Premiering in 1989, the series used the tried-and-true trope of having its teenage protagonist journal about his life to work through big feelings and coming-of-age woes. 

Meanwhile, this teen facing everyday problems like crushes and peer pressure was also a genius who had to also deal with the serious issues of being a licensed physician working his way through a difficult residency program.

The tension between the child genius’ intellect and social situations brought complex layers of drama and comedy into the series, and it ran for four seasons before getting cancelled in 1993. 

Neil Patrick Harris was a teenager in ‘Doogie Howser, M.D.’

RELATED: ‘How I Met Your Mother’: Neil Patrick Harris Secretly Pushed for Barney and Robin’s Relationship

Today, Neil Patrick Harris is probably best known for his work on the long-running and incredibly popular series How I Met Your Mother. When he was cast in Doogie Howser, M.D., though, he was just getting his start in the entertainment field.

In fact, he had only been in a few TV movies before landing the role, which proved to be a major boost for the young star. 

Harris was born in 1973, making him just 16 years old when he was cast as the young genius doctor.

One of the reasons Harris landed the role — despite some misgivings from network executives — was because he was so convincing at putting on the mature airs of a doctor while also coming across as an everyday teen. It was walking the line that made the show work. 

Max Casella was much older than his ‘Doogie Howser, M.D.’ character

Max Casella
Max Casella | Dominik Bindl/WireImage

While Neil Patrick Harris was an actual teen playing the role of Doogie Howser, the same can’t be said for his on-screen best friend, Vinnie. On the show, Vinnie is Doogie’s lifelong best friend and a stereotypically girl-obsessed teenager.

In real life, the actor portraying Vinnie — Max Casella — was actually 21 years old. By the time the series ended, he was a 25-year-old man. 

As Mental Floss reports, though, Casella really did look the part. He was “sometimes stopped by police who asked if he was joy-riding in his parents’ car.”

Plenty of people will pay big bucks to stay looking young, but some people are just born with a perpetual youthful appearance. For entertainers, this phenomenon can open up roles that might be closed off to most actors their own age, but the sword cuts both ways, and it can be hard for young-looking stars to get cast in more mature parts.