Off milk - is drinking it dangerous?

[threeleftfeet]

DS (3yo) just drank some milk which it seems is off.

At least it doesn't seem off in the bottle in the fridge, but it curdled so quickly in his cup I guess it must be.

Will it make him feel sick?

Should I worry / do something?

Perhaps there was a drop of something else in the cup that made it curdle (orange juice perhaps?) If the rest of the bottle seems fine then hopefully there is nothing to worry about. Not a lot you can do either way, time will tell but good chance he'll be fine