Happy Birthday, to who? is the tenth episode of Season 4.
The Lab Rats find out Donald knows their birthdays and one of them is coming up. They don't know who, so they break into his computer, but find out a bit too much about themselves.
Tyrel Jackson Williams as Leo Dooley
Billy Unger as Chase Davenport
Kelli Berglund as Bree Davenport
Spencer Boldman as Adam Davenport
G. Hannelius as Elena Davenport
TBA as Dill Davenport
Will Forte as Eddy