Cats in heat!

Question
My husband and I adopted two female cats back in January.  They are between 7 and 8 months old.  I believe one of them is in heat.  She is showing all the signs.  She's acting "very submissive" if you will.  Last night, I saw my cats licking on each other and grooming each other.  Then the other cat begin licking the genitals of the cat in heat.  Is this normal?  I haven't had a chance to spay them yet.  Should I be concerned?

Answer
Leah,

Yes, at least the one female is in heat, and, yes, these behaviors are all normal.  I would get them spayed as soon as possible so some of the other less desirable behaviors, e.g. peeing all over everything, trying to get out to become pregnant, incessant caterwauling, etc., do not even get started.

Best regards... Norm.