Why would you say this guys?

If a woman baked me cookies, I would bake her a triple chocolate cake, a chocolate pie and cinnamon raisin bread all at once with a wedding ring!

Dammit all to hell! Why can't somebody be this interested in me(and not be illegally too young)!?!?!?!?!?!?!

He was probably feeling you out, seeing how you'd react. (And I'd wager he does like you.)

If you want to be really quite forward, you could say "She's right; and you should!" or some such.

I'd bet he'll ask you as soon as he manages to talk himself into it. :)

probably shy, you should have said something like "haha why don't you?" playfully, then suggest something really easy like coffee or movies with a group. don't worry I bet you'll get another shot soon ;)

Maybe he was asking you out? Either that, or he just thinks of you as a friend and was commenting on the fact that his grandmother thought what you did was cute.