Hi all
We have two Rotties - one who is just over a year old, and one who is 7 months.  They are both boys, and get on really well. 
We were wondering why they howl at each other so much - the little one sits next to biggun and yelps at a really high pitch, this then gets the biggun going, and he howls and howls, all the time with little one yelping back.  This happens about 5 or 6 times a day, and although not a particular nuisance, it is infuriating that we don't know what it means!!

Any ideas?

Oh, and our Cocker Spaniel just sits looking at them both like they are mad!!  He doesn't get involved at all!

It is a matter of communication, the boys are having a chat.

Seriously it is used to locate other members of the pack and is or can be contagious like yawning. In this case it may be the pup is missing a member of the family and once he starts the other joins in not really understanding why either.

Would suggest that you use something to get his attention and distract him from this as in the future it could become a problem.

my girls sit on stairs and howl when i go out and also in car on way to park, once one starts the other follows!

I have a rescue Border Collie found in Wales, she howls at opera music and is brilliant at it.
She's our Welsh Singing Doggy

I always wish I had a camera handy to record them - I would get £250 on 'You've Been Framed' !!!

I've got a stunner of my Rosie on my mobile phone, I've shown it to loads of mates and they all say thats one for YBF'd, trouble is I'm such a numpty I don't know how to send it to them or put it on 'you tube'. My OH will put Radio 3 on (posh music all Opera type stuff) and Rosie comes running and starts singing her head off, the other dogs all look at her as though she's knitting with only one needle!