It sounds like it started out as allergic colitis (the bloody stool) which
most babies outgrow by 1 year of age, and now he seems to have more of an
"intolerance" than an allergy.

just my impression, as a mom of another baby with milk-induced (among
other things) allergic colitis.  As he just turned 1, we are planning to
test his reactions to his former colitis-producing foods soon.

--Robyn