Replacement characters that outlasted the originals

Trying to make a list of characters who came onto shows to replace others for various reasons, in the same, or similar, capacity, who actually outlasted their predecessors.

So far i've got:

• Natalie replaced Sharona on Monk in s3 and stayed till s8. I liked her better anyway.
• Mr. Furley replaced The Ropers who spun off into a show in s3 of Three's Company, stayed till s8, too.
• Rebecca replaced Diane in s5 of the 11 season Cheers.
• Woody replaced Coach, who RL/in universe passed away in s2 of Cheers.
• Roz replaced two previous bailiffs who RL/in universe passed away in s4 of the 9 season Night Court.
• Julie on Psych starting the second episode, replacing Det. Barry, who was transferred for having an affair with Lassie.
• BJ, Col. Potter, and Maj. Winchester all came on MASH about s3 or so and the show ran for 11.

Any help and all that, if you guys have any more.

Captain Jenko was replaced after the first season of 21 Jump Street by Captain Fuller for the rest of the 5 season run of the show.

Interesting one on Bones, as intern Zack Addy was replaced after s3 by no less than 10 other characters:
Clark Edison
Daisy Wick
Wendell Bray
Colin Fisher
Vincent Nigel-Murray
Aristoo Vaziri
Finn Abernathy
Oliver Wells
Rodolfo Fuentes
Jessica Warren
who rotated in and out, and all had their own storylines/character development, becoming integral to the show and main cast for the rest of its 10 season run.

Caitlin only lasted a couple seasons on NCIS. Her replacement Ziva, 8.
Ziva's replacement, Bishop, at 4 seasons and counting, has also passed Caitlin.

Rossi's been on Criminal Minds about 9 seasons, 3 times as long as Gideon.

Wesley replaced Doyle 9 episodes into Angel, and went on to remain for the rest of the shows 5 season run.