So I feel like in every new episode I watch someone new has moved into Meredith's house and, either I am missing these scenes, or they don't exist, but WHEN exactly do these new people bunk up with Meredith!? There is someone new in her house every other episode, and none of the dialogue in the show mentions "Oh Hey April is moving in" and now suddenly Jackson Avery lives there too? I even missed when Lexie & Alex moved in and one day I was just like "oh hey Lexie lives there too now." I just wish they would show us when/how they came about moving into Mer's house. It bugs me! Anyone else notice this?
They do show some, and do mention...It is a lil' bit of a bother, but it is stated sometimes.
I'm pretty sure they did explain Alex and Lexie and April and Jackson moving in to Meredith's house.
I think Alex was when Izzy bursted into Meredith and Derek's room in a towel and yelling and asking Meredith "Alex is moving in?" Meredith repsonded with "We can't leave Alex out living in wherever he was living. He's one of our people. "
As for Lexie, I think Derek brought her home. Meredith brought Sadie home and Derek brought Lexie home. She had no where to go. Meredith and Derek ended up having a conversations about bringing home a stray.
As for April and Jackson, Meredith brought them home and it was explained how their friends (Reed and Charles) just died and they need a place to stay.
These stories may not be exact, but it's close enough. At least that was what I got from it.