Hope the spay goes well today. I have had successful female-female bonds in the past but from what I understand it can be more difficult. Someone with much more knowledge than me can probably give you better info, but I believe it would be more successful if both were neutered prior to trying to bond, which means you'd need two separate places to keep them both until that's happened. I know with males they need several weeks post-neuter for their hormones to die down but I'm not 100% sure if the same applies to females (mine was already neutered when I got her so it's not something I've needed to think about for a long time). It's certainly not impossible but you have to plan for what you'd do if they didn't get on, which is the same for any bond really.
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