Over protective 2.5 yo male

Question
Hello,

I have two 2.5 male desexed boxers and a 4 month old baby girl. On the
whole the2 boys are very well behaved and trained. When i was pregnant my
red boy was very protective of my pregnant belly and would stand over me or
next to me when ever possible. He would show no aggression towards my
husband or anyone else, however if my brindle boy came to close he would
growl and even attack. We would show him this was not acceptable and he
would be placed outside for his bad behavior.

The red Romulus boxer still now displays this behavior around my daughter, i
don't believe it is directed at her, but when ever Abacus the brindle dog is
close he will growl. It appears to be worse when she is crying or in the bath.
He also displays a habit of trying to get in between her and myself, i am
unsure if he is trying to protect her or me. If it is me i fear he may harm her. I
am unsure what to do and how to read his behavior. Please help i love all
three of my babies and want them to be the best of friends.

Answer
This sounds not so much like protectiveness as possessiveness - a form of resource guarding.  Instituting a Nothing In Life is Free (NILIF) protocol - for both dogs - will help establish your role as the controller of resources; the dogs are not allowed to guard any resources, because they all belong to you.  If you're fearful at all, then a consultation with a qualified behaviorist is essential (and it's probably a good idea even if you're not fearful).

NILIF
http://k9deb.com/nilif.htm

Behaviorists
http://animalbehaviorcounselors.org/acabc_members/
http://www.inch.com/~dogs/behaviorists.html

Resource Guarding
http://www.veterinarypartner.com/Content.plx?P=A&C=153&A=2438&S=0
http://ahimsadogtraining.com/blog/resource-guarding/

Good luck!!