Energy bars in Episode One

FreddeN93

While in the drugstore in Macon you can pick up three energy bars, and give them to the characters. If you pick up the first one, and straight away give it to Clem by using the 'Give Energy Bar' option with the mousewheel she will take it and thank Lee. If you however go into a conversation with her afterwards, the option 'Can I get you anything' will still be there. If you click on it, she will say she still is hungry, because the first energy bar wasn't much. Lee replies with he'll try to find something else for her.

My question is, how come I can't give her a second energy bar? I went to grab one straight after she requested another one, but it don't give me any option to give it to her. Is it even possible? The way Lee replied to her made it sound like another quest.

Thanks in advance.