She's been unable to do so until now due to "grippe" aka the flu.
Anne has been exploring Green Gables and the surrounding area and is seriously in love with the nature, which is described wonderfully. She has time to play like a normal kid, and that might be a first for her.
Another piece of evidence for that "Secret Soft Spots of Marilla Cuthbert" essay.
Marilla dryly responds that she's not discouraged, and says, "When I make up my mind to do a thing, it stays made up."
Lovely woman. Should go meet up with a Mrs Thomas and Mrs Hammond. I'm sure they'd get along wonderfully.
Buuuuuurn.
If it's not okay for Mrs Rachel to insult Anne for her weight, then it's not okay for Anne to insult Mrs Rachel for HER weight.
Also reasonably, Marilla sends Anne to her room. Then, rather unexpectedly (to herself), she scolds Mrs Rachel for insulting Anne's looks!
And this I think is again very reasonable. Anne really can't go around yelling at everyone who insults her, because, unfairly or not, she will get a reputation that way.
Mrs Rachel has "brought up ten children and buried two" and she suggests whipping Anne with a birch switch instead of the talking-to Marilla has planned.
Charming.
Marilla is more embarassed than anything and has no idea how to punish Anne. She points out Anne has called herself everything Mrs Rachel said.
Suddenly Marilla remembers a time when she overheard an aunt say, "what a pity she is such a dark, homely little thing".
She admits Mrs Rachel wasn't right in saying what she did, but Anne can't be rude back.
Again, I don't think this is unreasonable.
And honestly Anne needs to learn the balance.
This is honestly a very fitting punishment because it's the absolute last thing Anne wants to do. And this is a relatively small stakes thing!
Marilla dryly says they're not in the habit of doing that and dungeons are scarce in Avonlea so she'll stay in her room
And that's where we end the chapter!