Phineas and Ferb (2007)

S2E25 Phineas and Ferb's Quantum Boogaloo

The boys venture into the future to snag a gadget, but when their future sister Candace discovers their secret, she realizes she can use this information to return to the past and catch them in the act. Once she makes it back to her own time, she quickly understands that she has made a grave error that only she can rectify.