Tantrums?

At what age are the screams & whines truly a tantrum? & is there something we should be doing at this age to curb them?

Here's the scenario: I pick up Colin from daycare & he's all smiles & squeals of happiness. The minute we walk through the front door at home, he's a completely different kid. What?! You want me to sit here & play? By myself? This is when the screaming & crying begins. It's to the point where he was coughing & choking last night. While I don't want to reinforce the screaming by picking Colin up, I do want him to know that we're there to care for him. I truly think he misses us all day & just wants to have some lovin' from Momma & Papa. But on the other hand, he needs to know that he can't be carried around all the time (it makes supper prep so difficult!). See the problem here? At what point is it normal "baby" behavior vs. a needy kid?

In related issues, any tips for getting CJ to stay seated in the tub? That's a fun new problem we've run into this week...