I've read some previous postings and info on the web about the number of
cats in a household and the dynamics between them.

We adopted two girls, about 6 months apart, in 2003.  The first was about
18-24 month when we got her in Jan. A few months later our eldest died from
kidney failure.  The second adoptee was a teeny-tiny kitten when we got her
in July.

A year and a half ago (Jan 2006) we found an orphan on our doorstep and
rescued her.  She and our youngest hit it off right away and were having a
blast smacking the stuffing out of each other and rolling and playing and
running up and down the hall for many of their waking hours and we did not
feel we could separate them so we kept her instead of adopting her out.

The two older ones sleep together and clean each other but the youngest gets
left out.  It may be her fault--I have seen her fight them off sometimes
when they do try to pin her down for a cleaning--but I noticed she does not
get the cuddly nap time with them that they do with each other.  I try to
cuddle her more and wipe her down with a warm damp washcloth once in a
while, but I'm wondering if we need to get her a "pet" of her own.  Since
she's the youngest, I wondered if a young cat or kitten, younger than her,
would help her have a better social life (and get bathed). Or will she just
keep up her stubbornness (she's the only cat I've ever had who growls.  She
was growling quite loudly out the front window today and I looked out to see
the UPS Man next door.  Sheesh.

I have allergies so we've never had this many kitties (I'm sort of holding
my own with the asthma right now) but I'm wondering if 3 is enough for
everyone to function well.

Okay, so having a fourth would be fun for us, too, but really, my primary
concern is the baby having more companionship.

Anyway, experienced input/feedback is appreciated.