I have decided that Calla should officially belong to Boo. She enjoys playing with her so much that I've given up worrying about what might happen. And as my husband rightly pointed out, I have a lot of other dolls.
Today we dressed Calla in some bright new Nellie-Rose Doll Fashions made by eBay seller maudie-mays (these are great for children as they're cute, colorful, and easy to get on). Then I helped Boo cut a fabric scrap to create a simple triangular headscarf and a sash, which she though was great fun. I'm planning to re-read the "Advice on child sewing for dolls" thread on Sasha_Mart, as I have a feeling that information will come in handy in the not-so-distant future. Once Calla was suitably dressed, they shared some tea and a few laughs in Boo's bedroom.